Unearthly by Cynthia Hand

This book was actually a reread. Clara is an angel-blood. Every angel-blood has a purpose to fulfill. She has these visions that lead her, her mom, and her younger brother Jeffrey to Wyoming. She is apparently supposed to save this guy named Christian during a fire, but she is confused as to what her true purpose is involving Christian. Of course, complications arise when she falls in love with Tucker Avery (her friend's twin brother) during the summer before fire season. She ends up faced with a monstrous choice amidst startling revelations!! I am immediately starting the sequel and I can't wait to find out what happens next!