I will try to sum up:
In the final chapter she attends a Bly-esque men's weekend retreat. The point of these is to allow men to get out of the "earn a paycheck, watch sports, die miserable" cycle; give men a place to emote with other men. Women, obviously, can emote like nobody's business. When no women are around, men can do a fine job of attending to each other emotionally.
Vincent obviously wants to stay in character at the retreat but the effects of what is going on around her, and inside her is overwhelming. She sees men crying and hugging each other and commiserating in the fact that they have no emotional connection with their children and the people in their lives and I think she herself realized at that moment that everything she thought she knew about men was not just wrong but a lie.
I don't know how widespread this is but when I was in high school in the early 80's, some of the girls got into self-mutilation. They would lay a burning cigarette on their forearm and let it burn all the way down, leaving a nasty and obvious wound. These girls were fairly popular and reasonably successful in school. It was their way of dealing with the pain of adolescence. Vincent's reaction to the intensity of the men's retreat was to ask one of the men to hurt her. She suffers a nervous breakdown and ends her experiments.
In this chapter more than any other, Vincent set out to learn about male privilege but wound up learning more about female privilege.
I don't mean to gush over this book; it does have some serious flaws and I found some parts offensive but it is interesting.