i agree with cynical. i also empathize with feeling that although you guys are messed up together, your relationship has it's fair share of dysfunction, those times together, the having that person in the home, in your presence, sharing quite companionship, feels really good.
and this statement, i completely indentify with:
i let the sense of relief that i felt everytime he came home take the place of an actual resolution to the problem for 3 f-ing years,
but if there is no real resolution, it's like banging your head against a wall and wondering why you have such a headache. or not wondering at all, but still being in pain.
so...maybe you're not ready to live a healthier life, inside of a more fulfilling relationship, or outside of one, alone and at peace with yourself. it takes time, practice, and a new mindset.
thanks for posting; i hope you have some better days soon.