Its like this - I KNOW I can be difficult. I have a couple of serious mental illnesses. I make sure that I accept my partner has to work harder then I do at our relationship sometimes. So my response to that is gratitude and appreciation. When I am doing pretty good is the time to talk to me about my issues. Also when I am doing pretty good is the time I do extra nice things.

A marriage is like 2 horses pulling a cart. They both have to work at it evenly or it runs off the road. Next time he says sorry is the time for you to approach him with the imbalance.