If the house is worth $150k and you owe 88k then you have roughly $50k equity if you were to sell the house (after selling costs). So in theory, you could buy him out of the house for $25-30k. You might be able to trade that for him not having to pay you alimony. Then the money from a roommate would cover most of the mortgage payment, no?
It also sounds like you have a good case for him to be equally responsible for the student loan debt since most of that money was used for living expenses during his illness. You'll want to document everything you can.if it comes to divorce he should be responsible for a share of that debt.
