This book is dark. It's terrifying and heartbreaking. I enjoyed this book, though I did feel vaguely unsettled laying down to sleep after I finished it. It's well written and the jumping back and forth through time left me feeling off kilter as I read it.
Possible spoilers in the edit
Edited to add: I've noticed people commenting on what kind of friends does she have that don't believe her and that this whole thing seems implausible. What was terrifying about this book is how plausible it really was. He was charming, had a good job, and was a remarkable actor. Her friends knew her as a party girl who never settled down. When she says she doesn't think it's working her friends encourage her to stay, and by the time it's really bad she's too frightened to go. This happens so much it's sort if a textbook example. Places like Shelterwings exist for this very reason. They have safe houses to hide these women and children, in extreme cases they change these women's names and move them as far away as they can. Domestic violence, stalkers, all of this is very real despite what you may want to believe. That's what made this so scary, how normal he seemed to everyone else.