Road blocked

We've known about the ADHD for several months now.  His biggest attempt in the matter is to "try harder" "do better" and "not treat me this way".  But as a result, we wrap around to the same issues, the same destructive patterns and the same hurt and painful feelings.  How much longer do I hold on?  What options do I have?  We are in the midst of rock bottom once again.  I am raw with hurt and pain from neglect, abandonment, broken promises and being taken for granted moment after moment that I can see leaving as the only alternative.  I do see the pain in his eyes.  I see that he is hurting too, that perhaps he is "trying his best" but is just spinning his wheels.  I have been kind.  I have been patient.  I have been hopeful.  But I can't force the medication, the counseling or the treatment.  It's lonely, it's just shy of abusive and I am not seeing a way to "calm down" and work this time through.  The hopelessness is overwhelming and I feel at this time I would be much less lonely if I were alone, rather than in a roommate situation.

Has anyone been this far down, and come back up again - when you aren't in control of the ADHD and their behavior, treatment or otherwise?  Any suggestions would be helpful.