I honestly believe that if they wanted to make it work after you leave they could. Their lives are not your responsibility. They could all get jobs, could all pay for the mortgage and food together. They could stop wasting money on pot. I'm saying this because you shouldn't feel responsible to them.

Perhaps you could talk to a lawyer about getting your name off the mortgage. This must happen all the time in divorces, someone should be able to help you.

I also think you should go home to Texas, by yourself. It is what you truly want. There is no guilt in wanting what is best for yourself or in seeing that this relationship has no future for you. You are your number one priority. I don't believe it is wrong to not care about this situation anymore. It seems like she never put much effort into caring...

(Side note, I'm very surprised that you put up with her smoking in the house at all; my dad has asthma, and before the state laws changed, we couldn't go into restaurants that allowed smoking regardless of where we sat because he would be so uncomfortable and have trouble breathing).

Good luck! Remember, take care of YOU!