It's very important to listen and observe w/o giving advice unless he asks for it. You did very well in listening and validating about everything is his fault.

There are several reasons why he can't sleep much and they are: 1) his mind is like a ping pong ball and it's bouncing/racing all over the place w/thoughts, etc.; and 2) the guilt of what he's doing or not doing has him in a dither.

I would continue as you have been and let him worry about whether the door is ajar or not. Some of these folks get a little more adamant about what they are doing when we advising them that we are leaving the door ajar or we love them and want them to come home. I suggest being silent on this one. He needs to sense that you are moving on and GALing. Treating you like a friend is typical behavior, but at some point, you'll have to decide just how much you want to go "dim" w/him. But, for now, stay the course. I know it's tough, but really you are doing exactly what you should be doing.

Continue to give him plenty of time and space.

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.