I liked the idea of this story, it had a lot of potential to be a phenomenal book but it fell short probably because the writer wasn't able to combine both the romance and the mystery suspense. I feel like she didn't place much importance on the emotions of the suspense part of the book. The supposed trepidation and stress of experiencing a murder or worry for the safety of a loved one didn't translate very well in the book.
For example

Spoiler

Having sex for the first time the day your best friend is violently killed seems uncaring and loses the opportunity to portray the grief that Tony should have felt, I understand it for the need to affirm life in the case of risk but when someone is in physical and emotional pain it seems like the wrong place to start. Also Marty's death was sort of pushed aside and Tony's grief should have been better depicted./

Spoiler