That was a very long post. I hope it helped to write it out. I usually does. There is a lot bottled up inside you and i get the sense that you are disconnected from support. It is so important to connect.
I dont know what to say about the self injury except that many people do that one way or another. I dont freak out about it because i think it seems to work for people who are experiencing very deep psycholocal and emotional pain. It usually means that the red light needs to go on. Meaning get serious help. Whatever that means to you. Religious, AA, Adult Children of Alcoholics, Survivors of Childhood Sexual Abuse.
You dont have to go around feeling this kind of horror. There is help. If it helps to write it down and you need witnesses, then do it here. No one, including me, wants you to hurt yourself. And frankly it probably scares the hell out of nearly everyone.
I hope you can get some specific help with the sexual abuse and the other childhood trauma. This board can help but you might really get some bigger help by also going to a compassionate and very skilled therapist who understands your issues and can help you out of the nightmare.
Take care,
Sea storm