There is this great memior called 'Sickened' about that bi proxy syndrome and it sounds to me like you need to get yourself declared 'undisabled' and get out of there.
One of the hardest things we have to do as ACOA is let our parents live their own lives because we can't save them, regardless of what they are doing or not doing, i.e taking medication, not taking medication, drinking or not drinking etc.... We can try to control them but it will drive us mad as control over another person is just an illusion.
Not only are they free to live their own lives, we are free to live ours too.
Bear in mind that God/Hp is looking after you both.
I for one will keep you in my prayers.
:praying