I know this is hard for you. He's not playing fair by just disappearing on you like that. You may have to look at not accepting him back. He obviously has no respect for you and your marriage. You need to be able to sit down and have him tell you what's going on with him. Then decided if you can continue to deal with him doing this to you.

I know it's hard to let go, my first marriage broke up after 24 years. But also you can't stay in limbo. The stress will take its toll.