I knew of a lot of abuse in my WH's past, but not to the extent I learned soon after D-day. It's horrifying and tragic, and I do think there is some connection..
But I was sexually abused as a child too.. The difference here is that I went to counseling and have been open about talking about it. I knew I needed help, so I went and got it and have been in counseling on and off since I was a teenager.
WH, on the other hand, said he never wanted to talk about it again. After we separated, I actually have a text from him that says, "Keep your damn mouth shut about that. I will never speak of it again."
I think it's great your H is going to counseling for it. I think it is possible for him to overcome it if HE wants to. No one else can make him want to or do the work for him..
What he is not allowed to do is continually blame his ADULT behaviors for things that happened to him as a child. We all have to take responsibility for our actions and not use our past as an excuse..
Good luck and big hugs to you guys..