You've been given very good advice from the posters.
I'm sorry things didn't work out w/your moving back in. Reconnection takes a lot of time and patience. It's evident that he's not any where near reconnecting and working on the marriage. It's good that you and your dog moved out. Maybe it's time for you to rethink the finances and allow him to take care of his own health insurance, etc. I know you and your h agreed on how the bills would be paid, but there comes a time when you have to cut the apron strings that he is relying on and allow him to learn how to walk on his own and be accountable for all of his bills. To him, in his frame of mind, he knows that he can rely on you to be there, i.e., as a mother figure.
The racking up of the credit card tells me that he's not learned the lessons that he needed to learn and eventually, he will meet the credit card limit and then what? Will he get another card or file for bankruptcy? You know him better than we do, but I would seriously consider, at this time, of getting all of my bills in my name and paying for them myself. He will eventually need money to pay his credit card bills and hopefully will not leave you hanging in the wind on your bills.
I realize that things might not have been great w/his parents in the picture, but when it comes to family, blood is thicker than water and generally, MLCers will tend to go with the option that is the easiest for them. I can't help but wonder is there something else going on w/him and his parents and he is using that as an excuse to detach from you. They will always be front and center in his life and maybe it's time for you to think about what you really want. Do you want his parents to be the ghosts in the room each and every day that you are w/him? Do you want him to feel like he has to choose between you and his parents? Have you spoken to his parents at all to get a better understanding of what needs to take place in order to have peace and harmony?
Just keep in mind, if the situation works itself out w/his parents, he may very well come up w/another excuse not to reconcile. They tend to find more and more excuses as we tackle each issue and it becomes very frustrating.
I agree w/the posters on working on your anger and resentment issues. These issues take up a lot of time and energy from a person who has these feelings. Continue to work on you, find ways to make yourself happy w/o him in the picture for the time being. If, and when, the time comes, you will know when to walk completely away. But, I do not think you are there yet.
Remember, this is not a sprint, it's a marathon and you can't rush the process. If you truly want to find a way to reconcile, then you have to leave him be to figure things out for himself. Going to self help seminars, etc., will not fix his issues until he's ready to truly do the heavy lifting and look within and do the work.
Keep the focus on you!
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.