Tears are my new best friend

Ever been tired of caring?
Well I am and what saddens me is that there is nothing I can do to stop it. I keep harming myself by caring about people who don't give a damn about me. She betrayed me and yet I still care too much about her. She sees me everyday and pretends like nothing happened. I cant even express my feelings because I'm scared she'll just call me dramatic . Seeing her so happy with other people makes me feel so sad, not because I don't want to see her happy but because I feel like she does not deserve to be this happy after everyday she made me go through...

If I have forgiven her then why does it hurt so much?
Does that make me a horrible person?
If yes, then does it mean that I deserve everything that's been happening to me?
Does it have anything to do with my bipolar disorder?