Lp, I'm curious -- What was it about the man he was whilst married that he didn't like? I hear that he wanted to make sure he was never that man again, what did he want to be? What does he mean by "the guilt of not being there"?
Do you know his ex and children? Do you agree with his assessment? Does he want to be a father?
I ask, as ever, partly just out of curiosity and of course partly thinking about my own situation; my H definitely didn't want to be who he was whilst with me, but has never said who or what he DOES want to be, I do of course understand that this is immaterial to my self, but it does make a difference to our children.
In my own case I tried to ask how he wanted to be a parent, what he wanted from me in that regard, I never got an answer, I did finally understand about not even asking the question. I've done my best to be the best person I can be for my self and our children, regardless of what he is or isn't doing.
And I recognise that my own situation is different, these were just a few things that jumped out at me.