I think the song is sort of like a sad story. In the second stanza where it says, "You fasten my seat belt because its the law. In your two ton death trap I finally saw, a piece of your love that bathed me in regret..." I think they both died in a car crash. Supporting lyrics directs me more to the thought that such did happen because right after the mention of the seat belt and two ton death trap this was next, "And we are so fragile. Our cracking bones make noise..."
So, I therefore conclude that the song is about a girl who realized that her man loved her in this split second when they where in a car and then suddenly right after, they met an accident and everything was lost which is why she sings that we are fragile and breakable girls and boys.