Eve Ensler has helped women all over the world tell the stories of their lives through the stories of their bodies. Her play, “The Vagina Monologues,” has become a global force in the face of violence against women and girls. But she herself also had a violent childhood. And it turns out that she, like so many Western women, was obsessed by her body and yet not inhabiting it without even knowing she wasn’t inhabiting her body — until she got cancer.