Water, this sounds so familar with some others here on the board that I can "steal" a response I gave to another a short while ago and paraphrase it slightly to your sitch.
Your H likes the way you are together now! but it appears (as is common) that H still looking for ways to admonish his fears that it could turn bad again. To him those bad times are demons. Demons that continue to haunt him. He still is fighting to be with you, but he has to find a way to exorcise those demons to be gone with them. His solution - Divorce himself from the old M, so he will have a chance at a new M without any possiblity of those old haunts coming back!
Water, keep remaining consistant with the "new" you. Time is the only tool you have to demonstrate to him that the good times are here to stay! When he starts to realize that then those D papers will lose their worth to him.
If he continues to press on moving forward with D, then it's not a matter of whether it is right or wrong ... its a matter of it being a solution he believes will work. If you can buy into this, maybe it might help in guiding your direction and still work towards moving closer together.
but it appears (as is common) that H still looking for ways to admonish his fears that it could turn bad again. To him those bad times are demons. Demons that continue to haunt him. He still is fighting to be with you, but he has to find a way to exorcise those demons to be gone with them. His solution - Divorce himself from the old M, so he will have a chance at a new M without any possiblity of those old haunts coming back! 
