Why do I feel this sense of loyalty when he had no issue leaving his family?
Because you were the one to stand up for your family? Because you are the healthier person? Because you are moving on with your life and can put things in perspective? Take your pick. I'm betting D) all of the above.
You have to decide what's best for you. You owe him nothing. How you treat him at this point is based on you living by your values. It may mean doing something that pisses him off or it may mean not and having to deal with the anxiety of him still being in your life. What will allow you to be true to yourself?
Me: 50 W:43 S6, S3 M: 12 yrs. T: 17 M is bad & Not happy Bomb Mar '14 S 5 Feb '15 D Bomb 13 Apr '15 (but "no hurry") DB Coach May '15 Wants proceed on D Aug '15 Starting 1-on-1 negotiations Sept '15