I have been in a similar circumstance when my 14 year old stepson, Doug, was hit by a car in 1991. He received a severe closed head injury. My ex-husband and I had custody of him and his older brother. Doug spent 5 months in the hospital, 2 in a coma and 3 in rehab. When he got out he had to go to therapy 4 days a week (physical, speech, occupational). Doug's father rarely participated in his therapy and rehab so I was the only one doing everything. By the time Doug was 18 I was exhausted, depressed and numb. I had 12 or so years of sobriety when Doug was 18 and I can tell you an AA program helps you through these things however, AA doesn't turn you into a professional caretaker.
Doug currently resides in a 4 bedroom home in a very nice neighborhood. There is a staff of 5 that cares for the 3 men living in the home. Doug will be there for the rest of his life. When he was injured he lost the functions found in the frontal lobe (judgment, inhibitions and the like). I know for a fact that I am not capable of a lifetime of caretaking and it is my firm belief that few people are.
I believe Doug is much better off with professional caretakers. I believe anyone with the severe symptoms you describe in Kay require professional care especially when you are talking about the safety of Kay and others, not to mention your own physical and mental health. I have already told you this in a PM before and I know that guilt and feelings of extreme responsibility prevent you from considering another choice. I hope that you will seek counsel on this subject and perhaps you will find that many people who care for their loved ones every bit as much as you, find they must turn them over to professional caretakers.
Regarding sobriety, you must ask yourself the difficult questions and seek quidance from your sponsor in this matter. I can only share my experience, strength and hope with you. My experience is that I know my limitations. I know I am not capable of properly caring for somebody for the rest of my life. I must be honest with myself about my capabilities and limitations when I am dealing with the care of another human being no matter how difficult these revelations may be. God is my strength. My hope is that the right answers will come if I listen and that the right people and circumstances will appear as they frequently have.
My prayers and thoughts and hopes are with you, 9G, and I hope I have not offended you as I have only the best intentions.