Have not read all the thread as its too long and too early for me.....

I think they are just selfish people, if they had been abused in any way shape or form, or not abused at all ! Its a selfish choice, they could choose not to do it and work hard within themselves or they can act it out.

So in my head its selfish people.

Yes even SA is a selfish abuse as they again have the choice to act on their illness or get help.