Can anyone list some songs about 'Being better off without someone?'?

a song like Since you've been gone by kelly clarkson. i need to find a song that relates to me and heres my quick story and this might remind you of a song. My best friend liked me and didnt tell me and she let jealosy get the best of her and now we are not friends anymore she was also a compulsive liar. so any songs come to mind?