This is a sad tale. So sorry for you and the kids blueholly. Also sorry to say it but it sounds like your husband is deep in the bowels of his addiction. You have directly confronted him about his obvious problem and he completely ignores you. I'm guessing that's because he's the breadwinner and uses that as his excuse to do whatever he pleases.
There's nothing you can do at this point to help him but you must do everything you can to help yourself and those youngsters. Start off by getting the retraining order. This will ensure that he maintains his financial responsibilities to his family even if he's not there. It's only a piece of paper but it will also afford you with some protection from his most probable unwanted and unwired contacts. Meth can cause people to get pretty violent. Don't get freaked out but be aware that his mind is not of this earth these days.
Protect yourself and your kids. What he's doing is selfish and unfair to your family but if his behavior is exactly as you describe then there's nothing you can do right now to make sense or reason with his addiction. He's gonna have to acknowledge his own bad choices when it all comes inevitably crashing down on him in a big mess.
So sorry again. Stay strong. If you take care of yourself you'll get through this. Good luck.