For me is When I'm Gone by Eminem. It describes perfectly how I feel. How it feels to have a favorite person. To lose her and know that it's all your fault, feeling guilty to the point that you want to commit suicide. I relate a lot to Eminem songs in general, which may be a weird thing for a young girl to say, maybe because he raps about very polarized feelings, like extremely hating his mother or his exwife, and loving his daughter to the point that disappointing her made him want to kill himself at several points of his life. 

Other song that I relate a lot to is Calm me Down by Mother Mother.