How do you explain all your problems with some ones actions, over, maybe 3 months, without being rambly and considered abusive by this person who is both abused-abusive and depressive but definately broke your trust and took away your right to feelings?
You probably can’t. There’s no way of interacting with someone that reliably controls how that person will feel, or what they will think of you. 
Instead of worrying about explaining all the things to this person, go spend your time interacting with people you actually like. It’s a much more effective way of finding happiness.
And here, “like” means “people you trust to treat you well”. 
People you don’t trust to treat you well aren’t worth your time. Particularly if they don’t trust you either and would like you to leave them alone.