Is She Really Just a Friend? When it comes to friendships, the gender barrier has all but vanished. Here's how to keep everyone honest Dave's been married to Sandra for 6 years. He's been friends with Hannah, an attractive, witty pal he met as a teenager, more than twice as long. The two chat weekly and have been known to close down more than a few bars together. Sandra's response? She rolls out the red carpet whenever Hannah's around. Then there's Lizzie and Joe, who grew close after meeting at work 3 years ago. They're each happily married to someone else, but the spouses aren't exactly buying the whole just-friends thing. Rather than playing the tyrannical husband telling his wife who she can and can't see, Lizzie's man has instituted a "don't ask, don't tell" policy. "I feel like a reluctant mistress, sneaking around to see Joe only when my husband's out of town," Lizzie says. "That happens every week, which is convenient for the friendship." From coed rec leagues to office cubicles, the friendship gender barrier is all but gone. Not surprisingly, though, the chumminess may not always be on the up-and-up. A recent University of Wisconsin at Eau Claire study reveals that men in relationships struggle with feelings about their female friends. "We found that the more the men were romantically attracted to their friends, the less satisfied they became with their primary relationships," says study author April Bleske-Rechek, Ph.D. In fact, 15 percent of relationships result from "mate poaching," another study shows. The problem may reside in our desperate attempts to disregard temptation. When you convince yourself that you'd never cheat, you feel free to share more and go deeper. "People think they aren't violating the basic code of being sexually faithful, so they don't put up the same defenses," says Ronald Potter-Efron, Ph.D., coauthor of The Emotional Affair. "They want to preserve the idealized connection with an opposite-sex friend." But this can wreak havoc in your primary relationship, he says. So is your friend worth it? And what if your partner has an office buddy? We asked the experts how to make sure a few opposite-sex friendships don't ruin your love life.