The man is suffering dementia and Parkinson's. There is mention of two daughters. Here's what it is like after you leave. We got you your divorce after you walked out. We sold the house did your action. Got our Dad the care he needed. This was your third marriage. Our Dad is in his final days. After leaving his family with you we had duty visits. As we had our families he was busy with you. He had very little time. Because you had your fun times. I see my Dad daily thank god you are gone and I get this time with him. His last years were with you. What he remembers is you. He wanders looking for you. He cries because he can't find you!! You were offered help but could not face anything that was not easy and fun. I love my Dad good and bad. I will sit in the E.R room with every fall as he is scared. Hold his hand even when he thinks I am you. I am his daughter. I will be there and have always been. unconditionally
There are definitely 2 sides to every story. If dad was rude and arrogant AND has some level of dementia--that is a lot to handle. I'd be careful to lay the guilt and blame on this woman.
If she was caring for him and he was not able/willing to take care of her in return..maybe walking away was a better choice for her.
I have a SIL who always tells people she only has 'one foot in her marriage' as this is a 2nd marriage for both her and BIL. She is not a CG by nature and as BIL ages, we see her pull away more and more. Nobody would be surprised if she cut and ran. BIL's health is not great.
It's good that your dad has you. Just let this woman pass out of your lives and don't talk of her to your dad. You can't make things better for him, nor bring her back. Just love him and let go of the anger.
When dementia happens, I think that we lose the person we loved. When there has been a long long relationship of many years (spouse or children) shared love and shared losses and shared children and all that goes with it, we can sometimes somehow go on with the support of the deep roots formed of that long life. We become then not so much husband or wife, but caregiver. I have seen so much of heroism on Forum. But I have witnessed also human limitations, and just cannot judge another I don't know.
I am so sorry for all the grief you are witnessing, and the losses for your dad, by your description, are heartbreaking.
Don’t waste your time thinking about his past relationship. Focus on him and comfort him as best as you can.
You can’t change the past. Yes, it may hurt. Make the memories that you have of you and your dad.