Gatsby, Sorry you have to be here - but this is the place to be if you believe in marriage.
One of the key objectives in DR is to GAL. You need to do that so you develop a support system. This site is great and you get lots of awesome advice. However, you need to show you WAH that you are not tied to him. Give him a reason to want to be with you. Show him what he is missing. If it doesn't work out with H you will still have a life afterward.
When you GAL you may find you enjoy life again and stop obsessing over you M. I'm trying to do this myself. Easier said than done. At present I'm in the "Fake it til you make it" faze.