Since you earn more, it is doubtful that the courts will order him to assist you with all the expenses...at best you might get an order for the mortgage, but good luck on trying to collect it.
What I would recommend is that you get him to sign a Quit Claim on the Deed and to surrender ANY and ALL interest in the property. While he would be legally entitled to half the equity in the property, I doubt there is much after 8 years beyond the initial down payment and I would put forth to him that since you are carrying the burden of all the expenses, that his share of the expenses will eat away at his share of the equity and by the time the house is sold, and those expenses paid for, he won't have anything left.
Once you get the QC, I would then either see if you can refinace to lower your payment or get a roommate until the house sells. And if he doesn't go for the QC, I would probably still look into a roommate.
If you air your dirty linen in public, expect people to comment on the skid marks!