10 points for best answer please i need a song?

This may not be exactly what you have in mind, but it's a great tune. The Animals, "Don't Bring Me Down."

http://www.youtube.com/watch?v=0FZU4JVOmro

I've moved off them in the past few years, but the song Unholy Confessions by Avenged Sevenfold pretty much fits the bill here.

It's about a a guy and a girl in a relationship and the guy realises that he doesn't feel the same after she's admitted all the 'unholy' things she's done in life.

She poured her heart out to him and admitted she doesn't care about the past, she only cares about the ones she loves. But the guy is torn, he wishes he didn't care about her past but it's killing him. And the thought of her past hurting him in turn hurts her.

The narrator does realise that his expecations of her are unrealistic, that he can't change who she is or her past, and he can't stop her sinning in the future, no matter how much she wants to change.

In the end their promises are broken and there is a lot of trust lost. They stay together, but the relationship can never be like it used to be.

Love will tear us apart,by joy division,an apt song,willcover most aspects,of what's interesting about a love song.