He is learning the hard way that his choices, behavior and words have consequences. He had chances in the past to change and didn't. The hard way is now his only option and the consequences are now piling up.
You have raised young adults (i think mid teens and early 20s?) who are strong and able to say for themselves that they have reached the point of enough is enough. That is not an easy thing to accomplish given the dynamic. Encourage them to keep processing their feelings. They can't change their father, they can only change themselves. It's likely that their father will never understand that he is the one responsible. Your children and you deserve peace and happiness. Its just going to take a bit of work to find it.
How are you coping through these changes? I remember the "eye opening" days and seeing all that I had missed in the past. It can feel overwhelming in both good ways and bad ways. It's very normal to hope things can be better. Just remember that your healthier and happier place in life is for you. He must find is own.