The Locket by Stacey Jay
Summary from Goodreads: What if you found out miracles could happen? What if you found out that sometimes, miracles are curses in disguise... One girl, two boys, and one very scary piece of jewelry.Although the summary doesn't give much away I'm intrigued by the pretense of two guys, a girl and whole lot of secrets. From the author of You Are So Undead to Me. The Locket will be released February 3rd 2011 by Razorbill.