Good songs about betrayal?

My ex is a lying . She broke up with me over a month ago claiming family issues, but she still wanted to be my friend. I just found out today that she started seeing someone else less than a week after she broke up with me. I did so much for her and I feel used and betrayed. The only way I can really express my feelings is through music, so I was wondering if anyone knows any good songs based on this subject.