G-money is dead on but I often post the statement below and ask yourself honestly if your H's actions meet any of the three criteria.
As you probably know, the only way he's going to overcome that deeply held belief is for you to open the cage door and completely cut him free. If you engage in a relationship with him again it should only be under the conditions that:
1) He sees you as someone of extremely high value 2) He views a relationship with you as something much better than a life with someone else or a life alone 3) He's willing to work to win you
Without those three things, he's going to walk again down the line, because he really doesn't have the motivation to work with you to change anything, your relationship will keep seeking the same equilibrium it has had because of how your personalities and issues come together.
I am not saying to throw in the towel but what I am saying is you have to let go of the fear. Be your best self and if he walks he walks and just know that you did everything you could to save the marriage.
Truthfully I think your H is a scared little (another name for a cat) who is afraid to make a decision and stick with it. He is searching for happiness outside himself and believes the grass is greener. Unfortunately these people (my EXW is one) will never be satisfied until they find out. That's why you have to open the cage door letting them know they are free to leave if they so choose. I am a true believe that true reconciliations mostly happened when two people have gone and lived separate lives for years and mutually agree that there lives were better together than apart.
