If I were in your place, I would probably let him know that I am am there for him and give him a little space. If you are concerned for him check in with other people that have contact with him and that way you can get updates if they are available. While waiting for him to decide what he wants to do with that I would talk to someone about my anxiety and maybe get some help in processing and dealing with the fact I have someone whom I care deeply for behaving in destructive behavior. If I wanted to make it work I would try to put myself in a better place to be prepared for the pushing and pulling that seems to be happening here. I hope you get some peace in all of this.