I think it may have a role to play... right along with heredity. My grandmother was bipolar, and I know that in many ways, her life was a lot like mine with the abuse, a screwed up family, etc. I was sexually abused by non-family members (people my parents trusted that they shouldn't have and by so-called friends) I've been in abusive relationships... it goes on and on and on... until the here and now. Remembering those times has had me crawling out of my skin as of late.