I had a lot of breaking up songs downloaded when I left my bastard ex husband. This is mine and my girlfriend's favorite. We actually changed the name of the song on my iPod to name it after him:
Naked Eyes - Promises, promises
[ame="http://www.youtube.com/watch?v=qJP2PH8WKaI"]http://www.youtube.com/watch?v=qJP2PH8WKaI[/ame]
This one is also very fitting: Beyonce - Me, Myself, and I. It's my new anthem.
[ame="http://www.youtube.com/watch?v=Dw74Wp29HX4"]http://www.youtube.com/watch?v=Dw74Wp29HX4[/ame]
I also like: Alice Keys - Karma
and Shania Twain - It Only Hurts When I'm Breathing