The risk of being murdered skyrockets the moment a woman tries to walk out the door. Michelle did not stay because she was weak, deluded, or foolish. She stayed because she had done the math better than anyone judging her from the outside ever had, and on some very rational level, she understood that her abuser’s threats were not empty.

I kept thinking about how many times I’ve silently wondered why a friend didn’t just go, and how ashamed I felt reading this, realizing I’d been asking a question that blames the person for surviving the only way she knew how.

2. Strangulation is a warning most of us have never been taught to hear.

There’s a detail in this book that I have not been able to shake, that being choked by a partner, even once, even if you don’t lose consciousness, makes you many times more likely to eventually be killed by that same person. It’s one of the single biggest predictors of homicide there is. And almost nobody knows this. Not the victims.

Often not even the police showing up on the scene, because strangulation frequently leaves no visible mark, which is, horrifyingly, where this book gets its title. No bruises. No obvious wound. Just a woman who was nearly killed with someone’s bare hands, and a system that looks at her and sees nothing worth escalating.