GM, There is no way to rationalize w/him about things. He's made up his mind that the only way to be happy and have no responsiblities is to get a divorce. I understand all too well how you feel. My xh was hell bent on a divorce from the day he walked out the second time. He had it all and our finances were in good shape. However, he told he that he might be making the biggest mistake of his life, but he had to do this right now. I guess doing this meant divorce of dabbling w/Twinkle Twat Ho.
Some will wake up just before the divorce is final and others will see it through, only to get so euphoric after the papers are filed (for about 6-9 months) and then years later come to realize what they've done and try to reconnect on some level. Others will ride off into the sunset, never to be heard from again except at holiday times.
GM, I hope that your h will wake up and realize what a wonderful wife, family and home he had. He has so much to lose in all of this. Please take care of yourself.
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.