“I’m reading this ‘He’s Just Not That Into You’ book and I’m surprisingly into it,” my friend Anna Jane instant-messaged me last week. Anna Jane, 24 and a fellow reporter, has written about weddings and engagements for several publications, and this year, inspired by the end of her own relationship, she created Breakupnews.com, a site that reports on acrimonious splits. “It’s reminding me how not into me Milo was.” I was floored. Anna Jane’s ex-boyfriend Milo was, in my opinion, many things: immature, commitment-phobic and the father of a baby by another woman on another continent. He was not the right guy. But he was really, really into Anna Jane.

I had heard a lot about “He’s Just Not That Into You,” the ubiquitous self-help book by Greg Behrendt and Liz Tuccillo, both formerly of HBO’s “Sex and the City.” The book was spun off from an episode of the series in which Carrie’s boyfriend Jack Berger tells Miranda that her date didn’t come up to her apartment for a reason no more mysterious than he “just wasn’t that into her.” Its message: A strong woman should stop imagining that the man in her life is treating her shoddily because he is busy, conflicted or suffering from bad cellular reception. She should move the hell on. Nip unpromising relationships in the bud by administering a brief, stinging torture (He does not like me) in place of an endless, agonizing one (Does he like me?) It’s not a bad plan, though the book also advises women to ratchet down the aggression and reverts to that old Rules chestnut: Don’t call him, he’ll call you … and fulfill your every wish if he’s into you enough.

Published in September, the book has become a bestseller, with a million copies in print; a major movie deal is almost final. The tome’s catchphrases (“Don’t waste the pretty!”) are peppering the female lexicon. One of my editors recently shrugged in response to a story pitch: “Eh. I’m just not that into it.” My exchange with Anna Jane suggested that the book’s philosophy had penetrated far enough into her psyche not only to make her reconsider her current dating life, but also to retroactively recast an old love affair. How could she reduce a relationship that involved so many heartbreaking complexities down to one simplistic evaluation? Does the book offer a one-line romantic litmus test that will free us all from regret and self-recrimination? Or is it just turning us in increasingly dizzying circles?

It made my stomach hurt. Were other people’s deliciously painful memories of failed relationships being wiped clean, “Eternal Sunshine”-style, and replaced with this one-sentence mantra? I sent an e-mail to a handful of friends asking them about the phenomenon and urging them to pass my query along to their friends. Within 24 hours my inbox and voice mail were deluged with messages from women I didn’t know. So great was the tidal wave of fascination with the HJNTIY craze that I received multi-paragraph missives and had long conversations about the book with women who had not read it.

Maria, a 34-year-old New Yorker, was freelancing at Barnes&Noble.com when she picked up the book out of “morbid curiosity.” “I had spent a lot of time waiting by the phone,” she wrote. “This book just tells you to stop.” Kristina Bada, 27, who works in television, said, “It gave me a huge self-confidence boost … If someone is truly ‘into you,’ then they will go through heaven and earth to spend time with you. They’ll go without sleep, they’ll travel if feasible, and they’ll do whatever they have to do so they can see you.” Jaime Licht, a 28-year-old San Diego law student, wrote, “Even my guy friends say it is incredibly accurate and are worried that college freshmen will read it and frat guys’ sex lives will disappear.” Twenty-four-year-old New Yorker Cara Lemieux wrote, “If only I could regain the hours I have spent overanalyzing e-mails, forwarding them to my friends, asking what they thought ‘he’ meant by a certain word or even the time of the day he sent the e-mail relative to the time ‘he’ gets into work … [it] saves time [and] empowers us by making us realize that we are not alone in our delusions, and reminds us that we need to stop behaving like ‘he’ is the only man on the face of the planet and we are privileged to have his attention.”

It’s the new Atkins: no more pasta, and no more second dates with men who do not hit Reply promptly enough. By phone, coauthor Tuccillo told me that after her agent read the book proposal, she dumped her boyfriend. Two women told me that HJNTIY has become their “bible.” And yes, many are turning the periscope over their shoulders and examining old relationships. They said that they now see old insults — forgotten birthdays and avoidance of family gatherings — for what they were: muddled enunciations of something their partners were just too cowardly to say outright — that they just weren’t that into them.

“We’re upsetting a lot of women,” said Tuccillo when I asked her about this relationship revisionism. But, she said, she is not shocked by how forcefully the book’s mantra is being bandied about. “I thought when I was typing this book out with Greg that it was going to change the world and revolutionize dating,” she said. “From the moment the idea came into the world, it seemed to be explosive.”

Cynthia Rockwell, 50, lives in Connecticut and is an associate editor for Wesleyan [University] Magazine. “I really wish that I had had this book back in my 20s,” wrote Rockwell, who is married to her second husband. “Oh, it’s all so clear in retrospect that I made excuses for guys who were really a waste of my time.” Rockwell recalled a loaf of bread she baked for her first husband; he didn’t eat much of it. “Duh! He just wasn’t that into me if he didn’t care to accept a gift I’d made for him and wasn’t concerned about hurting my feelings nor touched that I’d thought of him,” she wrote. Or maybe he just didn’t want the bread. No matter. Rockwell’s current husband is very into her. “Soon after we started dating, he gave me a mug w/ my name on it that he’d found in the gift-shop at the hospital where he works, clearly showing that while we were apart going about our day, he’d been thinking of me,” she wrote.

Martha Danly, a 51-year-old management consultant in Point Reyes, Calif., who said she does not watch television and reads the Economist and the New Yorker, had not read the book. But after receiving a forwarded copy of my message, she looked it up and was so struck by the title that she called to talk about it. Danly discussed a yearlong post-divorce relationship with a man who never said he loved her. “If I had read this book I would have said, ‘Let’s bring it down to what’s really happening; in the end you are not giving me what I want.’” Danly said it was empowering to a point. “But why not change the title to ‘You’re Just Not that Into Him’?” She added: “I think it’s important to ask women: How do we get hooked over and over again? We don’t just make this shit up! Maybe they should call it ‘He Is That Into You but He Cannot Express It.’ Or ‘I Just Don’t Think He’s Able to Be That Into You’ or ‘He’s Just Not Meeting Your Needs and Therefore You’re Just Not Into Him.’”

Of course, the authors of the book would tell Danly that in her enthusiasm for their message, she’s twisting it back on herself and making excuses: If he’s not expressing it, then he’s just not that into you. Eleven of the book’s 16 chapter titles begin with the mantra, each focusing on specific signs. He is just not that into you if he is not asking you out, not calling you, not dating you, not having sex with you, or having sex with someone else; if he only wants to see you when he’s drunk, doesn’t want to marry you, is breaking up with you, or has disappeared on you; if he’s married, a selfish jerk, a bully, or a really big freak.

I have actually known several really big freaks who were seriously into me. Be that as it may: HJNTIY’s message is loud and clear. There is something powerful about it, of course: a sense of freedom and self-worth that comes from stopping a loser relationship in its tracks. But the book’s repeated scolding can also make you feel as if you’ve been clubbed repeatedly until you just want to haul your un-loved carcass into bed. Lucia Smith, a 22-year-old coordinator of a New York pediatric literacy program, wrote that she “devoured” the book. But she sagely commented, “They could have written ‘Stop wasting your time because you’re clearly worth more than this, because any girl would be worth more than this’ in huge letters and called it a day.”

The upfront self-flagellation factor has made some women wary. One 34-year-old editor at a glossy women’s magazine told me she was scared to read the book. The editor, in the midst of a divorce, is seeing someone new and said, “I feel like it’s going to confirm that the guy I’m dating right now is not that into me.” She added: “I’m afraid I might reevaluate a lot of my past relationships too and feel bad about myself for staying in things that weren’t that great … Even with all my experience working on these kinds of [relationship] stories, I’m afraid I might not be able to totally resist it mentally.”

It is hard to resist. It plays on our psychological default setting: He doesn’t like me. We women love to swallow hard truths about ourselves. It’s not masochistic, exactly; we just believe that we can take it and that we must remain vigilant about unpleasant realities. They’re good for us, like soy milk and crunches. Julie Rottenberg and Elisa Zuritsky, the “Sex and the City” writing team that penned the original “HJNTIY” episode, argue that the HJNTIY mantra is the opposite of masochism. “The fact that this has become a phenomenon says there was this huge level of denial and deluded optimism at work,” Rottenberg said. Zuritsky continued, “What we have been doing to ourselves is masochistic. This lets you off the hook and cuts off the urge to pull yourself apart and try to correct the actions that might have caused him to not be into you.” Yes, but only if you can stop that 3 a.m. voice at “So? He didn’t like me. Big deal!” before it drops an octave and murmurs, “But what if I were skinnier?”

The important, honest truth in the book makes the frenzy around it all the more complicated. Because the authors are right, and funny, and incisive! The no-excuses Behrendt and hard-sell Tuccillo really do understand men and women and have taken careful stock of their arguments. Smith, the pediatric literacy coordinator, said that since reading it, she’s been giving her friends, especially the ones “dating married men or throwing themselves at men who literally said, ‘I don’t love you, I’m moving away, I will be dating other people,’” “slightly meaner” advice. HJNTIY may be the best friend of the best friend: a necessary manual for all of us who have wanted to take our sisters by the throat and say: “Shut up! He is never going to call!”

But sharp as the book is, it also feels — as Smith says of her new advice style — slightly mean. Melinda Arons, a network news producer from Washington, D.C., and a HJNTIY convert, told me that “to have someone lay it out for you and be brutally honest about it is a liberating thing.” When I asked her if the message was a little, you know, soul-killing, she said, “I don’t think the authors intended for it to mean that the person has no love for you or no affection for you. Your boyfriend could be into you, but are they into you to the point where you’re feeling fulfilled? If you’re not, don’t feel bad that you have standards, and move on.”

Ian Kerner, a sex therapist and the author of “She Comes First,” will publish a response to HJNTIY in February. “Be Honest: You’re Not That Into Him Either!” will be released by HarperCollins’ ReganBooks. Kerner, 38 and married, acknowledged the fundamental truth of the original book’s message, but said it’s presented in deeply flawed ways. Kerner objects to Behrendt and Tuccillo’s advice about not making phone calls or being aggressive. “It’s like they’re telling us to sit back pulling petals off daisies: He’s into me, he’s not into me…”

The book’s push for passivity is in fact startling. At one point, Behrendt suggests that readers write down five good reasons to call the man in question, then wait an hour and ask themselves, “Do I seem pathetic? Do I sound like someone who doesn’t trust my own innate hotness? Yes, you do! Now put your dialing finger away, get out of the house, and go find some fun!”

“[The book] felt so prescriptive and so goddamn cocky and like such a simplistic view of life and love,” Kerner said. “Any relationship comes down to two people and backgrounds and context and how they meet, and to reduce it to a set of rules … There’s something insidious about it … It is disempowering and a lot like “The Rules,” and it sort of leaves all the power with the guys.” As a sex therapist, Kerner said, he finds that both genders fall “prey to complexities and vulnerabilities, and men wonder how to be masculine and what to do. So I would hate for a woman to read that book and think that any guy that doesn’t call simply isn’t into her. In some cases it might be true but definitely not always.”

As for the book’s resemblance to “The Rules,” Tuccillo said, “We were all obsessed with “The Rules” when it came out because it was telling women to behave as if they had self-esteem even if they didn’t have it. The criticism of it — which is valid — was that the goal seemed to be only to get a man. And ours is pretty much the opposite. We’re saying ‘Move on, sister.’ And not just ‘Move on so he’ll come back.’ Actually, ‘Just move on.’” Rottenberg and Zuritsky, the episode writers, maintain that the beauty of the HJNTIY rule is that they’re foolproof. “I don’t fear that someone’s going to take this too far, because let’s say you decide, I haven’t heard from him all week, so I’m going to move on,” Rottenberg said. “And then he calls. Well, that’s great too. Nobody’s saying you should burn him in effigy!” “Or burn yourself in effigy,” Zuritsky added.

All these circular arguments are particularly funny in light of the simplicity of the original HJNTIY message. “The authors never mention that the character who originally spoke that line was Jack Berger,” observed Lea, a 31-year-old publishing executive. “He was the utterly self-obsessed and emotionally immature asshole writer who broke Carrie Bradshaw’s heart with a Post-it note. So he’s the wise man? He’s the truth teller?”

Turning to the original text does problematize the whole He’s Just Not That Into You thing. In the episode in question, Miranda indeed finds liberation in Berger’s revelation. But she later applies it to another guy, who’s running off after an Indian meal. It turns out he has diarrhea. It’s part of the joke of the episode: No edict, no matter how revelatory, can be safely applied to every situation. Sometimes he really just has to go.

It’s sad to compare that carefully observed truth to Behrendt’s Dr. Phil commando parenting-style response to “Nikki,” one of the book’s fictional complainants, who “writes” that her boyfriend doesn’t pay attention to her because he is “totally important and totally busy.” “Too busy or important to ask you out or call you — what a catch,” Behrendt responds. “Congratulations on your quasi-relationship! It must feel amazing to know that you’ve been programmed into the super hot and important busy guy’s cellphone, even if he never uses it to call you. You must be the envy of every woman he’s really dating.” Behrendt’s tone is a bracing slap administered by a man to the face of a hysterical woman.

In Carrie Bradshaw’s universe, that’s not cool. “Sex and the City” was a cultural salt lick for a reason. It took old notions of female hysteria and frivolity and turned them on their heads. It was never about desperation or insanity, but about what happens when complicated people collide and each collision forms something new: new pain, new fun, new sex, new commitments, new disappointments.

And much as the women I heard from this week kvelled over how the HJNTIY balm can erase all the painful uncertainty from our lives, I have to ask: does leaching the complexity of life always bring relief? I don’t think I’m alone is saying that sometimes tortured romantic plotting is fun. And OK, when it’s not fun, at least it reminds us that we can feel. Making outrageous suppositions and creating fantastical narratives and theories about what’s going on in our love lives can occasionally feed a very real hunger for something to think about other than our jobs and ourselves. We all may be superfoxy and unimaginably desirable, as HJNTIY repeatedly assures us. But sometimes contemplating our wonderful selves gets old. And that’s when we drum up some drama.

Maybe I’m just weakly reassuring myself that all those rakes out there really did love me. But I’d like to point out that “Sex and the City” ended with its heroine, Carrie, in the safely adoring embrace of one Mr. Big — a man who spent six seasons illustrating nearly every one of HJNTIY’s chapter headings. He broke up with her (repeatedly), did not call, married someone else, had sex with other people, didn’t want to marry her, disappeared, was “totally important and busy,” and was a selfish jerk, bully, and really big freak. Big told Carrie in as many cowardly ways as he could conceive of that he was totally Just. Not. That. Into. Her.

And yet…

When those inevitable reboots of beloved franchises come around, die-hard fans and newcomers get a chance to return to the roots of a character and glimpse the glory yet to be. They’re all about how one becomes a legend — and they’re wildly successful. Spider-Man. Superman. Batman. Carrie Bradshaw.

Wait, what?

It’s true — this week, the long-threatened “Sex and the City” prequel — “The Carrie Diaries” — got a green light from the CW.

“Law and Order: Criminal Intent” certainly had some hubris this week, making a “Spider-Man: Turn Off the Dark”-like musical the scene of the crime and placing “Sex and the City” star Cynthia Nixon in the center of suspicion as a drunken Julie Taymor stand-in. “Icarus,” the season finale, is set in a world where “Turn Off the Dark” already exists, so there are various references to both its massive flop and Taymor’s illusions of grandeur. In the opening scene, we see a bleached-blond  sitcom star absolutely ruining Nixon’s vision!

June 3, 2001: Carrie Bradshaw and her three best friends hit HBO’s run … er … airways once again, beginning the fourth season right as Sarah Jessica Parker’s character was turning the big 3-5. “[It's] a landmark age for women,” Parker said during an interview about the episode, (titled “The Agony and the Ex-Tacy,” woof), “It makes her think about choices she makes and what she doesn’t want to repeat.”

“Chick lit” is one of the most depressing terms I can think of in the publishing industry. Then again, I don’t know that much book-selling jargon, so there are probably worse ones (“Magical tweenism?”), but that phrase — applied to frothy writing about “modern” women (and their love lives) –  is almost a derogatory term, implying the type of fluffy romance masquerading as post-post-post-new-wave feminist spiel. Yet for some reason, agents are encouraging female writers to think about chick lit marketing when writing their first books. I mean, no one is denying that the genre has mass appeal. But you know what else had mass appeal? “Two and a Half Men.” And Hitler.

(The author chose to use a pen name for this piece.)

Six and a half years ago, my first and only marriage detonated after only 14 months. My ex-husband, a recovering alcoholic with, it turned out, much bigger mental problems, left in a spectacularly sudden and cruel fashion. He said he’d never been attracted to me, and he told lies about me to his family and friends, and he left. I was lucky, empirically, to get off this easy and only lose a little over three years of my life to the debacle, but the shock of it was deeply traumatic and I was shattered. I was 34.