Unconditional Love. It speaks volumes. I only wish I could do it better.
When my Mom was dying, I had my daughter tell my ex that he could visit her but maybe let me know so I wouldn't be there. Because she still loved him. He declined. But it tore him up. The week before she died, my dad and I talked about it. He said that if ex wanted to come to the funeral home - he and anyone else should be made welcome (tough for me at the time but agreed upon). He declined that too. But I have to say - he did phone me when he heard she had passed and he cried more than anyone else. I think it would have been easier on him if he had just come to make his peace then. He did send cards and make a charitable donation which was decent.
I think your wife is handling things well. And your father is a gem!
Take care of yourself Wii. Try to enjoy him while he is still there. Party rather than grieve. Share those memories. There will plenty of time to cry.