He can't co-parent right now so don't expect it. And really if he views being with his son as helping you out, did he ever co-parent. Remember, don't go to the hardware store for bread.
You will learn to take care of you and going to AlAnon is a start. Tell him whatever you need to tell him. What are you afraid of? And I mean that seriously, if he has a history of physical abuse that changes the picture.
You are in my thoughts. Did you look at the online AlAnon page?
Me 57/H 58 M36 S 2.5yrs R 12/13
Let me give up the need to know why things happen as they do. I will never know and constant wondering is constant suffering. Caroline Myss