The so called demons that he is revisiting are the ones from his past. The crisis is all about his childhood/past. The one ingredient that makes up the crisis throughout the entire time is depression. He can run, but he will not be able to hide from those childhood traumas for very long. He must face those traumas and accept that he is not at fault for them and accept that he was just a child/teen when they happened.
You have to remember, this is not your journey and you can't fix him because you did not break him. He has to do the heavy/deep work on himself. Your journey is an opportunity to do the things that you have not done for a long time. What types of things did you enjoy before you married your h? Now is the time to rediscover yourself and those things that you have put on hold.
Trust me, it will be a while before your h figures himself out. Right now, you will not be able to figure him or his past out. One day, when he feels safe enough to talk about his childhood, he will. Right now, he is still running and smoking pot is just a band aid for what ails him. They will try many things looking for something to ease the inner pain.
Keep the focus on you and let go, let God have this situation. There is nothing you can do but listen when he wants to talk. Do not judge him, but just listen and if he wants your opinion, then give it to him. Until that time occurs....continue to move forward with your life.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.
