Hi Spook. I'm sorry things didn't get any better while you were away. I'm afraid I think it is going to take much longer before your h even starts to grasp the consequences of his actions.
I agree with what others have said. Now it is time to focus on yourself and the boys. Plan your life assuming he will not be part of it, and let him do (as dollyd says) the work of winning you back, if he manages to gain enough maturity.
You mustn't waste another moment in worrying about what will happen to him, or hurting his feelings. And don't entertain for a minute these suggestions from him and his cronies that you might be to blame for anything. You can hold your head up high as you have kept your vows and been faithful to your commitment, you have conducted yourself with integrity.
Now he is a big boy and must look after himself. You must take each day as it comes. I know it doesn't seem like it right now, but these life-changing, devastating happenings also represent opportunities. When you have healed enough to be constructive again, revive your dreams and ambitions and make them happen. I was a single mum for years, and despite the hardships it is also a rich life with much freedom. It may not be a freedom you would wish for but nevertheless it can be a valuable thing.
Remember I am here for you any time you want a few days away, with or without your boys.