Honestly don’t know what to do

I have been with my partner now for over two years. He has been diagnosed with ADHD since he was a child. He has the hyperactivity part but I've seen this side slow down with him dramatically. I recently walked away from our relationship. He seems to always put everything and everybody else before myself and my son. In the first year I had him calling me names (his never been physically abusive) when he gets frustrated with me, he also tends to go through these really high periods where he is happy and fine and we go well through these periods (I should mention his not on any medication or therapy) and then he somehow gets down in the dumps and becomes very distant and shuts off from me and it makes me feel not loved at all. When I ask him to spend time with me he will do so but with a extremely passive aggressive attitude. If I bring up something in a calm non judgemental manner I get stonewalled by him for a few days as punishment and he is a terrible communicator tends to forget to tell me things which will generally important. He has cancelled our wedding twice now because his scared and I had enough of been let down so we had a reasonable fight and I went down to the beach to cool off and came back to our house and he had taken all of his stuff emptied the house from all of his stuff this is the first time his ever done this and it hurt me extremely badly and broke my trust with him. I also found out he had been bad mouthing me to his mates behind my mates and they had started attacking me and stalking me and threatening me and he just stood there and wouldn't stand up for me at all. It's been a horrible two years. So I left and returned back to my home state but now I have him calling every night and wanting me back and I found out he has taken himself to the doctors and has been referred to a specialist for ADHD to see what is suitable for him medication and or therapy. I honestly don't know what to think or whether this is all a big trap, he is a good lier as well I've caught him out several times it's destroyed our trust.