Paul,
I wanted you to know that reading your profile helped me somehow. I am the BS and our story has similarities to yours from the abusive alcoholic father to the OW who threatens suicide.
My WH was/is full of issues: denial, low self worth, insecurity, compartmentalization, and feeling overly responsible for other people's problems.
It's like he needs to grow up all over again, but the right way with himself as his own parent.
Some books that have helped us so far are:
Emotional Blackmail by Susan Forward
Adult Children of Abusive Parents by Steven Farmer
I have thought a thousand times how much easier this would be if we were tackling WH's issues without the pain and anger caused by the affair. I could have been strong, supportive, patient, compassionate . . .
But the truth is, he wouldn't have faced his horrible childhood unless he absolutely had to. He was an expert minimizer and had convinced himself and everybody else that he had overcome the past.
Welcome to SI and hugs to you and your BS. Somehow, it helps to know that other people with a background like WH's have affairs despite great marriages.