Damon's Betrayal

Damon Salvatore, a mysterious dark vampire who after years of searching, found love within Elena. She's in college now, but something about Helena, girl down the hall, has him going crazy. He can't compel her, his senses heighten up when she's around, and he feels his body remembering glimpses of his human self. Who is this girl? And why can't he get her out of his head?