No, no, no. None of the above. The answer, according to author Greg Behrendt, is that he's not really interested.

Doesn't matter why. No ego-soothing platitudes. No pop psychology. No cute relationship tricks. He's just not that into you. The truth will set you free, but first it will make you miserable.

The tough talk is tough love for women from Behrendt, who strips away all the excuses for men (why he didn't call, isn't faithful, disappears, won't commit, etc., etc.) in the new book, "He's Just Not That Into You: The No-Excuses Truth to Understanding Guys," so women will stop wasting their time on the wrong guy.

The Los Angeles comedian was a bachelor for two decades before settling down. By his own admission, he was guilty of plenty of bad dating behavior — which made him a perfect consultant to the HBO series "Sex and the City." For the last three seasons, Behrendt advised the show's all-female writing staff, sitting in on script-writing sessions and providing "straight male" feedback.

"The biggest lie of all is 'It's not you' — because you are the person I'm in the relationship with. The truth is, 'It is you, and I'm not into you,' " says Behrendt, 41, now a happily married father of a 2-year-old daughter.

About 18 months ago, Behrendt listened to the female writers ("All sharp, all attractive, couldn't have more going for themselves," he says) discuss a guy who had gone out with one of them, kissed her, then declined to come up to her apartment because he had an early meeting. No call the next day, but he sent an e-mail a week later.

The women all reassured her that she was fabulous and that he must be scared or really busy. Behrendt knew no morning meeting will keep an attracted man from a midnight mambo. "My first thought was, 'I don't care if I'm flying the space shuttle tomorrow, I'm coming up.' "

He broke the news: The guy wasn't into her.

The writers gasped. "We were horrified," remembers Liz Tuccillo. "It was like we were all punched in the stomach. Then we started laughing." The cruel reality descended on the room. Each woman grilled Behrendt about her own relationship, and each time he shot down all the sympathetic excuses. The bottom line: If these men were truly interested, they would call, be faithful, commit, and more. It was just common sense to him, but a revelation — like cracking an ancient, secret code — to the women.

"He's just not that into you" was written in a sixth season script of the show, the blunt answer to Miranda when she puzzled over the baffling behavior of her new beau. Tuccillo (41 and never married) was so taken with the idea that she decided to write a book with Behrendt detailing the many variations of "JNTIY" in relationships. "I had so many years and years of making excuses for men," she says. Writing the book with Behrendt forced her to break decades of bad habits.

To wit: While working on the manuscript, Tuccillo mentioned that a new guy promised to call over the weekend. "It was Sunday night, and he hadn't called. I was bummed out. On Monday night, he calls and I'm overjoyed. I tell Greg, 'That guy called. I'm so happy.' And Greg's reaction was, 'But he didn't call you when he said he was going to.' "

Tuccillo was annoyed — at Behrendt. "You are such a drag, Greg," she told him. "Give me a break. He was off by 24 hours." But ultimately, Behrendt was right. "He's the big brother you wish you had. He's demanding these men treat you the way you should be treated."

There's plenty of dating advice, mostly for women trying to deconstruct the hearts of men. The premise is that men are complicated, emotionally stunted creatures incapable of direct action. And so women spend years obsessing with understanding girlfriends, wildly hoping that deep down he's really in love and wants to be with them. Even if he doesn't pick up the phone.

People always want to know, "What happened?" Nothing happened, says Nancy Kirsch, senior vice president of It's Just Lunch dating service. "Ultimately, chemistry is impossible to predict. That's what it boils down to.

"I hate to think that someone thinks they did something wrong or something not right enough on a date. That's just not the case." But women, she says, are much more prone to second-guessing than men. "We want to try to figure it out. We want to fix it." And they so want to believe men are telling the truth.

Behrendt believes men would rather chew off their arms than admit the truth. Why do they lie? Not just lie, but kiss and compliment and generally mess with women's heads rather than say, "I'm just not that into you"? He thinks it's fear of confrontation. "I can't even tell you why. Men are afraid of women being upset or yelling. In a fight with a guy, you know what it is: It gets verbal, then it gets physical. With a woman, you don't know where it's going to go, and you know it can't and shouldn't get physical."

Relationship correspondent Jon Platner, in a column on AskMen.com called How to Reject the Girl You Don't Want, concludes that honesty can make women defensive and confrontational. "She may also ask you countless questions about what she did wrong, a situation you definitely don't want to be stuck in," he writes. He prefers Option 2: Give her gradual hints such as not returning calls, saying you just got out of a relationship and are hesitant to leap into another, or are too busy with your career. Says Platner: "This is ideal because it ends the relationship without you having to outright reject her. But even if she's slow to get the hint and it still comes down to you spelling it out, at least you will have softened the blow."

So it's better to lie? Or not call? Or just disappear? Well, yeah.

Behrendt admits he was one of those guys. He doesn't remember cheating on girlfriends, but "other than that, you can mark me down as all of them." That is, until he met his wife, Amiira, six years ago. He was really, really into her from the very start.

"It was like being brought up from the minors to the majors," he says. "She was just 'it.' I was able to envision a future with her almost immediately."

She operated at a certain level, and he had to step up to that level. "I really had to be a better man, all the way around, to be with her," he says. "Other women in other relationships would suggest changes that I wasn't willing to make."

When a guy is truly interested in a woman, he pursues her. That's the way it's always been, he says, and equality hasn't changed it. And so Behrendt strips away the excuses:

If a man is into you, he'll ask you out. (In fact, Behrendt believes no woman should ask out a man who hasn't asked her out first.) He will call, no matter how busy, because you'll be a bright spot in his day. He will want to have sex with you, and will stop having sex with other women. He will want to be with you when he's sober, not just to party. If he's really, really into you he'll want to marry you. He's not into you if he's breaking up with you, or disappearing, or married to someone else, or abusive.

There are exceptions to every rule, he says, but he really wants you to ignore them. You might be wonderful, but many wonderful women are in relationships with men who don't call, don't bother, don't care. It's wiser, he says, to assume the worst: You're the rule. He's not that into you, so get out and find someone who is.