Fallen (by Lauren Kate)

This book gets a 4 star review.

For young adults who like romance that depends on mystery, a mysterious boy hiding a secret that will change her life.

Luce didn't kill him. Why would she kill her own boyfriend? It was the shadows that did it, the same shadows that have haunted her for years. They started the fire that killed her boyfriend and made her end up Sword and Cross boarding school, a school for troubled kids. Kids who apparently killed people. But then she meets Daniel, and things change, he pulls her into a world she could only imagine. And why is he so familiar? It's like she knew him in a past life, did she?