Illustration: Emily Flake

A girlfriend of mine moved to Manhattan after graduating from college a few years ago. She began dating a guy who claimed he was separated from his wife. Except he, uh, forgot to let his wife know about their little status change. It didn’t tip my friend off that he never asked her back to his apartment—he wasn’t wearing a wedding ring, so he must be separated! Oh such sweet naïveté. Six months later his unlocked cell phone dialed his marital home from his pocket just as he was telling my friend he loved her—and his wife picked up. Oops!

While everyone has secrets, it seems to me that NYC denizens have an easier time keeping them (unless they leave their cell unlocked, of course). Maybe it’s the sheer number of distractions. Maybe it’s the confusion of more than 8 million lives intersecting at various points—some more sordid than others. It’s a big city, we tell ourselves. Who’ll find out?

Secret lives include gambling or drugs or a My Little Pony fetish, but mostly the things we keep quiet involve dating and sex. Three words: Craigslist Casual Encounters. Yeah, the Internet helps. Find me a person without a secret Gmail address and I’ll show you my grandmother. She’s the only one, I assure you.

J., 44, says he’s juggled up to “25 women at once” on Match.com, in addition to regular “AOL chatroom hookups.” So 1996! He continues, “My personal favorite is Craigslist. I responded to an ad that said, ‘24-year-old female needs short-term help.’ Turned out this girl was a young college grad living in NYC who couldn’t get her life together. Her father was a multimillionaire, but she hated to ask him for money because then she’d have to admit she was failing, so she decided to sell herself on Craigslist for $500. We had a regular thing for a few months, then she faded out. But can you blame me?”

Another e-mailer just offered one line: “I had sex with my boss on the Brooklyn bridge while engaged.” Yikes.

Another told me he had slept with his colleague in the fashion industry, “so she could get back at her lover. It backfired on her—he wouldn’t divorce his wife.”

And then there’s M., 34, a recruiter, who stumbled upon his married coworker’s open Yahoo account to find a draft of a Craigslist ad “Seeking Lunchtime Head” in the Men for Men section. Wow.

But it’s not just men. I know one gorgeous Manhattan socialite who’s juggled more than a few ménages à trois with her steady significant other—she also has boyfriends on the side. I know a big-shot businessman with a reputation for being a ladies’ man who let a male friend go down on him one evening. I know a controversial Manhattan wife who bamboozled her famous hubby into marriage by poking a hole in her diaphragm and baby-bumping it to the altar.

And those are tame: The blind items that would really shock you don’t seem fit for print. See, that’s the funny thing about secret lives. They’re seedier and more twisted than an episode of All My Children—but despite being unbelievable, they’re oddly commonplace. You think you’re the only one? You’re not. Just like everything else in New York, someone out there has a bigger secret life than you.

As for my secret life? That’s one secret I’ll never tell.

E-mail her at julia@timeoutny.com.

See previous Julia Allison on dating