This song is really about edward's point of view, you see, "you're leaving me breathless" that's when edward need not to breath when he's with bella or else he can smell bella's scent and otherwise, he might kill her. Andd, from my reading all the twilight books, it didn't say that bella doesn't like edward, she really likes edward. Edward does not know if he wants bella's body or bella herself, so the song is really from edward's point of view and not bella's.