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Cheating is something that happens to women. Women are abandoned, scorned, discarded, left. Men are the actors, the cheaters, the seed disemenators—the doers doing those they aren't supposed to be doing—that is, if you rely solely on information gleaned from film, music, magazines, stock photos, and candid conversations you've overheard at brunch.

The most popular and enduring images of infidelity are of women reacting to their betrayal: politicians' wives standing behind their men both literally and figuratively; Angela Basset pouring lighter fluid on her husband's car and clothing in Waiting to Exhale; Bette Midler, Goldie Hawn, and Diane Keaton dressed entirely in white, singing Lesley Gore's "You Don't Own Me"; and every devastated and bedraggled woman doing something sad and desperate in every Tyler Perry film ever.

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But, contrary to conventional wisdom, women cheat. Women delete texts, pretend they have to stay late at work, and steam up motel rooms with the best (or rather the worst) of 'em. Whether it's because of standard-issue gender stereotyping or enduring myths about female sexuality, we often don't hear their stories. Who are these Sarah Marshalls, these man-eaters, these she-devils, and why are they unfaithful? We wanted to find out, so we spoke to a few relationships experts, both women and men, on the subject. While all unhappy relationships are unhappy in their own way, we honed in on four common reasons why women cheat.

A) They're Seeking Emotional Fulfillment
"Women have affairs when the relationship is not addressing their needs," says Susan Shapiro Barash, author of A Passion For More: Wives Reveal the Affairs That Make or Break Their Marriages. "I've rarely spoken to a woman who describes her lover as similar to her husband; rather he provides what the woman can't get in the marriage." Conventional wisdom holds that women crave emotional connection, that they lust for intimacy and stability, while men are like Tex Avery cartoon wolves, howling and hitting themselves over the head with a sledgehammer whenever a cute gal crosses their path. Men pursue sex. According to infidelity expert and The Cheat Sheet author Stephany Alexander, women cheat in the pursuit of appreciation and attention. "If women are looking for another relationship and/or have a current unhappy home life, they tend to be more aggressive with infidelity," she adds. In other words, a woman's love is like a plant: If you stop watering it, placing it in a sunny window, plucking off its dead leaves, and talking to it in a low pleasant voice about Making a Murderer fan-theories, the plant will die … or it will start Facebook messaging Thad from SoulCycle.

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B) The Sex Just Ain't Cutting It Anymore
The problem with Reason A is that it fails to take into account what science, Carrie Bradshaw, and even pre-teen girls know: women are sexual beings. Women enjoy sex and women want sex—and not sex as a means to having late-night conversations about one's dreams and daddy issues but sex as a "Please god, don't let it end" end in itself. "Women, like men, also cheat because sex gets boring in a relationship," University of Winchester Professor Eric Anderson explains. "An uncontested sexological finding is that the longer a couple is together, the less frequent and less intense their sex will be. Sex with another is hot, in a way that sex with your partner is not." Barash agrees: "Sex-driven affairs are the currency men have traded in for years. Now many women seek the same satisfaction. If there's not enough sex at home, there's always the lover." Sometimes a couple's sexual drives just aren't compatible. If the square peg isn't going into the round hole enough times a week, a woman may stray.

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C) For the Excitement
Even if you are entirely smitten with your partner, even if you have no intention of ever cheating, it's likely that you chronically dream about someone else, someone who isn't much more than a vague sketch of a real person, like the woman who stood behind you in line at Starbucks this morning. Nothing is more seductive than potential and the new. We're all just magpies, beguiled by the unmarred shiny thing because it holds promise and it may be able to make us shiny, too. When it comes to affairs of the affair, difference is a draw; "If your husband is a truck driver, you might be having an affair with your professor from your literature course. If your husband is older, your lover might be younger. Or vice versa," Barash says. As the idiom goes, the grass is always greener and the guys are always better listeners and more inclined to go down on you and sincerely interested in the vegan chili recipe you found on Pinterest on the other side.

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D) Because They Can
In A Passion For More, Barash dissects what she calls "empowering affairs," or infidelities provoked by a woman's desire for liberation and control. According to Barash, a woman may take a "boy-toy" because she feels she's "entitled." This is a different kind of leaning in, one that finds its most accurate expression in Ciara's iconic 2006 anthem "Like A Boy." (A song that ushered in feminism's fourth wave.) In a complete violation of staid gender roles that contend that women's constitutions are too fragile for desire and sex, some women feel more powerful and confident when they are unfaithful or, as Ciara would say, when they're "out, four in the morning, on the corner rolling," doing their "own thing." The act of cheating is alluring. Women are rarely given the space to indulge their impulses or act selfishly, particularly sexually—to do so illicitly, without apology or consideration of another's feelings, is freeing.

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E) Other
Academics, experts, and princesses of crunk have their theories, but what of the real women who hope their boyfriends don't figure out their iPhone passcodes and lie about being with friends when they were getting drinks with a guy from work. How do they rationalize their actions, if they do at all? "Honestly, when I do think about it, which isn't that often, I—I know this is terrible, but I don't feel that bad," says a woman we'll call Hannah, reflecting on a year-long affair that ended her relationship. "It didn't really mean anything. It wasn't planned or thought out. I loved my boyfriend but I had this undeniable sexual chemistry with Mike. Love had nothing to do with that. In a way, being with Mike made me a better girlfriend—I was happier and calmer."

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When presented with the preceding expert-generated list of motives and asked which she identifies with most, Hannah demurs. "Sex is never that easy or one-to-one," she argues. So if this were a Scantron test, she would choose E) Other? "'Other,' yeah, definitely," she laughs. "I wish I had a better way to explain myself, believe me—I wish I understood! I wish I had a clear reason for my ex's sake but every explanation felt both true and silly. At the end of the day, he felt like he wasn't enough and that became the truth, you know? So we broke up."

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