Originally Posted by Erato
I guess my only option for now is to avoid the Ex or set some strict boundary with him until my man is ready to talk about this. I know that this is only a stop-gap measure but I'm out of ideas.
You're in a long-distance relationship with somebody with mental health issues who is making a good faith effort to work on them, and that you are unwilling to break things off with. You got into this relationship while you, presumably, still had feelings for your ex-.
Look, I normally am an enthusiastic advocate for poly- people pushing their partner's boundaries, but in this case you are really correct about what your only option is.