Lots of question, Ab. But it seems to me that your timeframe and expectations are not in sync. i.e. it hasn't been very long since the end of a 20 year relationship and you seem surprised to still have feelings when things come up that involve him.
"Does he hate me? Why?" Who really knows, Ab? He may not even know if he hates you and if so, why. But it's more likely he hates himself and anyone around him. That seems more common. Along with taking it out on you while maintaining a facade of happiness.
We can only hope that one day it is no longer a facade for them and that we won't care either way. It takes a lot longer than a few years to get there though. At least in my experience.
It's likely you feel these feelings surface when you have to deal with him or something about him. Seems normal to me, if that helps.
Peace, AJ
P.S. She has nothing on you. In fact, if she fits the pattern, you will likely find (much later) that she is more broken than he is and he picked her for some other reason. Again, I doubt it has anything to do with you Ab. Hard as that is to hear.
"Our lives begin to end the day we become silent about things that matter" MLK Put the glass down... "Yesterday I was clever so I wanted to change the world Today I am wise, so I am changing myself."