As you are already aware, they don't know which end is up and their minds change very quickly. I know you need to understand what is going on, but you are definitely searching for a needle in the haystack. We all have been right where you are and can understand the "need to know/understand".
About him moving back home, he needs to go back to where it all began and if that means moving back there, then he'll do it. It also means reconnecting w/the people he complained about. What you will find interesting, when he moves back, he will think that they are all great and what he disliked before has been thrown out the window. It's their way of trying to relive their past lives and yes, back to the time whereby they were stunted emotionally. It's very sad, but they have to do this to better understand themselves and also to find themselves.
For now, I would try to keep my anxiety level on low. What he's doing is very normal for someone in MLC. I would continue to try to focus on yourself and keep moving forward. Right now, he's exploring a world from his past and no one knows what he'll discover while there. We can only hope that he finds his answers and begins to grow up and want to return home to his family.
