My life will end if I can't be happy, yet everyone leaves me

My whole life, people leave me. I trusted my dad so much, he did terrible things to me and also checked out entirely of my life. My boyfriends leave. My last one did after three years and I thought he was the one who wouldn't give up on me healing from my PTSD. And he did. It leaves me feeling so worthless and that I'll always be left by those who love me. I thought for a minute of killing myself tonight because the anger and sadness is ruining my life. I can't deal and I'm not moving on because I'm so angry how everyone does this. I'm so alone. I'm living in a place with people very different from me, it's hard to find friends. I've never felt so lonely before. I'm taking me anger out on people, and nobody deserves that but I feel this anger will never end and I will get in so much trouble if I don't stop harassing others.