Vanna Le interviews Niobe Way, author of Deep Secrets: Boys’ Friendships and the Crisis of Connection:

During late adolescence ... boys begin to lose their closest male friendships, become more distrustful of their male peers, and in some cases, become less willing to be emotionally expressive. They start sounding, in other words, like gender stereotypes.

When they talk about intimacy that might remain in their closest male friendships, they use the expression “no homo” to underscore their heterosexual status. Questions about close friendships from the interviewers become, for the boys during late adolescence, questions about sexuality. Many of the boys in our studies spoke about feelings of loneliness and isolation during late adolescence and how they missed their formerly close male friendships. We heard these patterns of loss and distrust right at the moment in development that the rates of suicide among boys in the United States jumps up to become four times the rate of girls.