This book is simply not good. I haven't read Audrain's debut yet, but it seems that this one is universally disliked more than The Push. It was a struggle to get through this book, having to force myself to pick it up again, despite there being very little for a strong hook, and there being no positive occurrences to give the reader any tonal relief from the very tragic and upsetting storylines. 
The best characters, the ones who were the most sympathetic (Mara and Rebecca), do not get enough page space, and their stories both end incredibly ambiguously, to the point of the book feeling unfinished. The other two protagonists are unlikable and irritating and seem to chronically make terrible decisions, with little to no consequences. Every single marriage in this book is fucked up, and it creates an incredibly cynical overtone to the book (as someone who is in love and thinking about the future, man this book was a fucking bummer). 
Also, there were no thrills or good reveals. I feel like given her previous book, this is marketed the same, as a thriller with plot twists, but everything is really obvious, and the ending is incredibly anti-climactic. There is no good build-up, no shifting from the main uncomfortable tension, and no happiness or solid resolution to be found on any of the pages. 
Terrible stuff. Happy I finished it, but unhappy that I read it.