Yea.... I have experienced what you are going through....
But I must say not as well as you are handling it. I struggled to let go, and yes in the end I did let go and have never looked back but it took so much to get me to that point.
Think of it this way hard.... you are doing him a favor. Not only are you taking care of yourself but you are freeing him to live his life .... perhaps there is another person that will accept what he has to offer... you on the other hand need a more healthy relationship and that is good that you can see that. Letting him live the life he wants will help him to be happy and I have no doub in my mind that you will also be happier when you are living the life you want.... especially when you find a partner that does give you want your looking for.