I don’t know what’s best for you either. But I do know that you are asking the right questions. I do understand that it complicates things immeasurably that your husband now may not be able to control his violent impulses. My guess is that you could manage the odd and unusual. It’s the impulse control and anger issues that make the situation harder. You’re trying to figure out how to be compassionate toward him and at the same time protect your children from a distressing to dangerous situation.
From my point of view, the welfare of children comes first. You now understand that your kids have already watched their mom be in a relationship that is physically and emotionally abusive for many years. That’s been their model for marriage and family and unless you do something about it, they are apt to repeat it. You need to find a way to show them that treating people you love that way is absolutely not okay. At the same time, you want them to learn that a good person doesn’t abandon a partner when things get rough. Balancing those two issues is your difficult dilemma.
If your children are being emotionally or physically hurt by him, do consider whether there are alternative ways to provide care for your husband without living with him. If you haven’t already, I suggest you contact The Centre for Neuro Skills. I don’t have personal experience with this group so I can’t offer an endorsement. But I have looked at their website and it looks like a good place for you to start looking for more services and practical help.
I wish you all well.