Trusting, What an interesting time you had today. Sounds to me like he knows that he's messed up and was projecting his thoughts about himself on to you. Baiting is part of the package. They do tend to bait lbs to see if they have changed or if they are still holding the anger and resentment towards them. I'm glad you didn't take the bait.
I find the effort of attempting to get the hitch off your vehicle quite interesting. He really is trying to do something "nice" for you. I think he's feeling a bit guilty for what he's done and is trying to regain a little bit of ground w/you.
Trusting, take each day as it comes and accept him for who he is today. Sounds like life has caught up w/him and he's turning into his father. I wonder if he's still exercising or just sitting around since he's loosing a lot of muscle....listen to what he says and if you can, sift through the garbage and will get an idea of where his head is at during the conversation.
I'm glad today is over for you. You handled the situation extremely well.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.