I appreciate the kind words. I'd like to think life is the rock tumbler that polishes us into precious stone.
I am not the OP, but my guess is s/he benefits more from it than the parent does. As the old adage says ...
"Anger/hate/unforgiveness is like drinking poison, expecting the other person to die."
Please understand I am not judging you at all. To be honest I don't know if I would look after an abusive parent or spouse. I would like to say I would ... but truth be told I don't know.
What I do know forgiveness is a wonderful thing, and the forgiver gets way more out of it than the person who is forgiven. So much pain and conflict in this world is stems from humankinds seemingly innate inability to forgive, sometimes even after centuries have passed.
Edit: I don't know why you were downvoted and don't think you should have. If it helps, my posts in this thread have been heavily downvoted.
Also upvoted both of you FWIW.
Compassion, and peace with the way life occurs. I hope you find peace one day as well.