I'm sorry to hear that CL.
Perhaps now is the time to start making a plan. When you are looking at the big big picture, it can certainly feel like you are trapped, but that's probably not entirely accurate.
First thing would be a consultation with a lawyer, most will do a consultation for free. Find out what the laws are in your state with regard to separation and/or divorce. What are the property laws, would you need to sell your house, for instance and split the proceeds.
Secondly, is it possible that if you do decide to separate that you could move to a state where you are near more family members? Do you work or could you perhaps find work. Is there family in another state you could live with until you got on your feet?
I know the timing is completely off and the last thing you want to do right now is move, but this will pass and things will get better.
Small steps will get you moving forward.