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When Deborah Tannen, a linguistics professor at Georgetown University, was in grade school, one of her best friends abruptly stopped talking to her. Tannen and the friend, Susan, had done everything together: They had lunch together, made trips to the library together, did afterschool activities in their New York City neighborhood of Greenwich Village together. Then, one day, Susan cut her off. They wouldn’t speak again until more than half a century later.

Tannen recounted this story as part of a talk Tuesday at the Aspen Ideas Festival, which the Aspen Institute co-hosts with The Atlantic, about the sociology of friendships. Specifically, her lecture was about the gender differences that inform how people relate to and engage with others close to them, as based on her new book You're the Only One I Can Tell: Inside the Language of Women's Friendships.

As distressing as it was, Tannen’s estrangement from Susan—and, namely, the mysteriousness that surrounded it—wasn’t unusual. Women, Tannen has found in her research, are far less inclined than men to explain their reason for breaking up with a friend. Women are more likely to avoid confrontation; they don’t want to give their friend the opportunity to defend herself.

This is where women’s friendships—which because of their emotional intimacy can, according to Tannen, be far more gratifying than those between men—get especially complicated: Not knowing why a friend is ending her relationship with you, she said, “is really hurtful because knowing what’s going on is a big part of friendship.”

It’s a common belief that men are more competitive than women, but Tannen’s findings suggest that the reality is less clear-cut. Women are simply competitive in a way that’s less obvious—they’re competitive about connection. Among women, prized is the degree to which one is privy into the details of her friends’ lives.

This, Tannen says, makes them more prone to “gossip,” but it also means they can serve as immense, unmatched sources of support for someone who is going through something difficult and needs to vent or seek help. For example, say a woman gets into a series of disagreements with her roommate that culminate in an explosive falling-out; now she’s debating whether to break her lease and move out. If she were to confide about in a male friend, chances are he’d respond by giving his advice right off the bat; he might not know how to engage with her emotionally. If the woman were to vent to a female friend instead, though, that friend would likely request more context and ask how the issue makes her feel before jumping into her feedback. That willingness to take the time to hear her out first sends her what Tannen calls a “meta-message”—it tells her that her friend cares. One of Tannen’s interview subjects described this dynamic when reflecting on how she mourned the death of a close girlfriend: The hardest part of her dying is that “I can’t call her and tell her how terrible I feel about her dying.”

So whatever happened with Susan? Tannen decided to track her down as she was finishing up You're the Only One I Can Tell—doing so was necessary for the sake of research, Tannen reasoned half-jokingly. After some failed internet sleuthing, Tannen solicited the help of a friend who had a knack for tracking down immigration records (Tannen remembered that Susan’s family had immigrated from Iraq); finally, Tannen found her and asked her what had happened those many years back. It turned out that Susan hadn’t been upset with Tannen, but had felt pressured by her family to quit the friendship.

Susan’s family was very conservative and wouldn’t have been thrilled knowing that Susan was spending her afternoons gallivanting with Tannen all around Greenwich Village. So, one of Susan’s brothers ordered her to stop; if she didn’t, he threatened, he would  tell their parents. So, worried that her parents would punish her by forcing her into an arranged marriage right after high school, Susan cut Tannen out; Susan wanted to go to college instead, and to choose her own husband after that.

Today, Susan and Tannen are friends again. And the new friendship is likely just as gratifying as it was when they were in grade school.

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