Confused Relationships/Situation-ships

Hello, 

(Backstory) Previously I posted about my ex that left me for another woman and told me that we were broken up. He had a regular habit of blocking me on everything when he was upset and would unblock me when he was ready to talk or pretend that he never did that (the blocking or the cheating). 

I mentioned how I tried to move on after about 6 months passed. Since then, the guy I was seeing clarified he doesn't want anything serious but also wants to continue with things as they are without title or expectation of things changing. Suffice to say: just friends.

My ex returned, proposed to me with a ring, something I had always wanted and asking me to move in and get married right away. I asked for time to think about it after everything that had happened and now he's upset I said I won't move in right away and took that as me not wanting to be with him. He called me his fiancé over the phone, but now he's brushing me off like night and day after a few days. I just don't know what to do.. I get so much anxiety from his night/day changes, everything about him changes, including his decisions or things we discuss whenever his family gets involved. We could have one plan and that plan suddenly be nullified. Or he could be in his own head, which I can understand is something we all do from time to time but I still do my best to discuss things with him and not just spout plans. 

My friends are not happy about this turn of events. Our kids are upset and confused. We just want to be happy and live in peace but each time it's like the universe is against us.