It's your call. This may sound weird but I think many of us have PTSD. Living through the many many tramas and adventures an alcoholic puts us through is also a Post tramatic stress. We are mentally tramatized too. I guess I'd explain it just that way. Would he invite the source of his stress back into his life?
It's too hard to seperate the person fromt he behavior. It's the behavior that is tramatizing us.
My point, you have post tramatic stress too, that's just the truth.
People need their safe space. That doesn't mean you can't communicate and that he can't remain active in his kids lives.....from a safe distance.
Time will tell and when you don't feel at risk of being futher tramatized...maybe.
It is very likely that your kids have post tramatic stress disorder too.