Alzheimer's father, Alcoholic mother, I Am The Only child. The nastiness, bitterness, foul language, cruelty, that I have experienced over the past several years. My life that I have built is going down in flames. They provided me a wonderful childhood but I cannot forgive what I've been put through these recent years. How does one move on and how much does one sacrifice....?
Sacrificing your own well being is not part of this picture. Martyrdom is Not Required.
Dementia is beyond your father's control. He did not ask for this hideous condition, and he cannot help the behaviors it causes. There are different opinions about the extent to which alcoholism is a disease and how much it is within the alcoholic's control. Let us agree that whatever the cause your mother is "not in her right mind" when she drinks. Her right mind is what you saw in her kindness while you were growing up.
So you have two people you love very much who are out of their minds and doing hurtful things to each other, and to you.
1) Your first moral/ethical obligation is to protect yourself. You deserve that in your own right, and also if you go down your parents will have no advocate.
2) I don't know if you have any legal obligations in this situation. Just the obvious things of not exploiting their vulnerabilities, etc.
3) In my view, you have the moral/ethical duty to protect your parents from their own disabilities, to the extent you can do that while still protecting yourself. This may involve turning some of your concerns over to appropriate agencies/authorities.
As to forgiving them ... if Dad were causing you all kinds of heartache and extra work because he had renal failure do you think you'd need to "forgive" him? How about if he had cancer? Hepatitis? Personally, I think it is critical and essential to accept dementia as a disease outside of the person's control. That makes a difference in how we relate to them.
Your mother is doing very ugly things right now. I suspect that in her present state she can't help them. I guess whether you need to forgive her depends on your opinion/attitude toward alcoholism.
Holding on to the anger and the hurt, no matter how justified, is detrimental to your well-being.
Put on your own oxygen mask first, then help the passengers around you. Do what you need to do to keep your life from going down in flames. Then do what you reasonably can to honor your parents by seeing to it they get the help they need.
Somewhere there needs to be official intervention with her.
Really, from the outside..it looks to me like as she goes down in flames...she will take someone with her..if not your Dad, then you will be the one. Yes, protect yourself...maybe by getting her into a residential program for her too?
I find myself wondering how their life went so off-track. They went from being good parents to being cruel, abusive parents. I imagine it has a lot to do with the dementia and the alcohol. Both of these things can change a person dramatically.
The main thing you can do is decide how much you are willing to do for them. You have the right to leave if they start treating you badly. No one has the right to treat you badly, even if they are your parents. You can tell them you'll be back when they are in a better frame of mind.
Giving advice is such an easy thing to do. I know it is hard to actually follow the advice, though, when it comes to our parents. We get caught between being the responsible adult and the willful kid. If you are anything like me, no matter what you do you'll feel like you're wrong. We just do the best we can at keeping good boundaries up around ourselves and walking away when they won't respect the boundaries.