Lana Del Rey - Born To Die -- in the end of this video it is suggested that the couple MIGHT crash in their car, then the next time we see them, he is holding her bloody, dead body as we pull back ---- soooooo much more powerful than seeing them crash.
Noah in her desert oasis home. The hitchhiker calls her "The Girl with No Name" (after Clint as "Blondie, the Man with No Name") at one point because he realizes he doesn't know her name yet. Or she won't tell him. We all realize we don't know her name.
Nina Simone - Ne Me Quitte Pas (with lyrics) -- mixed with The Godfather theme is Noah's theme (it's the culmination of a teen's misunderstanding of relationships and love and being left alone/people leaving her and this dangerous thing that comes to the surface and hurts the people around her)