Certain female archetypes capture men's sexual imagination because they represent that elusive thing men can't have. Among them: the porn star (for obvious reasons), the nun (for obvious, more disturbing reasons), and the lesbian. For Dudus Americanus, this last image tends to conjure up the predictable girl-on-girl fantasies that have consumed him since he first stumbled upon Dad's secret stash of Oui magazines. But what about the guys who manage to break through? Is landing a woman who once found gratification in her own sex really a cause for celebration—or something more like trepidation?

Paul Mattingly, a 34-year-old actor, was doing "Klingon work" at Star Trek: The Experience in the Las Vegas Hilton when he met Anne, the pretty young manager of the attraction's gift shops. He chatted her up at a party (out of costume) and found out she'd dated a few other guys at the Experience, which didn't bother him. But after he and Anne became serious, he learned she'd been romantically involved with a woman for years.

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"There was a minute there where I had a little Ben Affleck Chasing Amy moment," says Mattingly. "It was this feeling of 'Clearly, this person has out-experienced me—is that going to come back and bite me in the butt?'" Five years later, it has not; in fact, the two have been married since 2007. And while Anne admits she will probably always be attracted to women, he isn't worried. After all, the Mattinglys now have celebrity analogues. After three years as one half of the most famous lesbian couple ever, Anne Heche ran off with Ellen DeGeneres' very vagina-less cameraman Coley Laffoon. When she split with him, she didn't seek comfort in the arms of someone of her own gender—but instead shacked up with Men in Trees stud James Tupper. Even Ani DiFranco, folk guitarist, feminist icon, and prominent bisexual, just hitched up with a man for the second time last January—in freaking Hawaii. And Lindsay Lohan—well, these days it's safe to say Firecrotch will take whatever she can get.

There are no reliable statistics by which to gauge how many refugees there are from the isle of Lesbos. Nor could there be: Bisexual women, for instance, don't have to "switch teams" to enter into relationships with men, even if they've lived with other women for decades. But if the hasbian (and for simplicity's sake, we'll include bisexuals who've shifted from women to men) really is having a coming-out moment, it might be because the lesbian had her big coming-out moment in the nineties—the decade that saw Cindy Crawford shaving k.d. lang on the cover of Vanity Fair, the birth of Lilith Fair, and the mainstream popularity of lesbian-friendly folksingers like DiFranco, the Indigo Girls, and Dar Williams, not to mention a slew of literal "coming-out moments" set off by Ellen's "Yep, I'm gay" in 1997. Today, The L Word has come and gone, Katy Perry has qualified her confession about kissing a girl with "I hope my boyfriend don't mind it," and the tabloids are far more preoccupied with LiLo's dropout antics than with her sexuality—just as we are more compelled by Rachel Maddow's intelligence than by her orientation. It's safe to say the novelty has faded. A woman who began her sexual exploration in the lesbian-leaning nineties would be in her thirties now. Is it unreasonable to suggest her biological clock could also affect her sexual proclivities?

"It's impossible for women reaching their child-rearing years not to be aware of that at some level, and to have that influence who they're with," says Dr. Lisa M. Diamond, an associate professor of psychology and gender studies at the University of Utah and the author of Sexual Fluidity: Understanding Women's Love and Desire. "I've seen bisexual women who say they could go either way, but as they get older, that structures how they want to be and who they want as a partner. The standard first question, Mattingly says, is "Aren't you afraid she'll go back to dating women?" "Continued change is really the norm," says Diamond. "We have this notion that as people get older, things stabilize. Not so. Meredith Baxter just came out at 62."