You feelings are very normal.

I’m facing the same situation with a sister who recently became estranged. Our mother didn’t do one thing to help, and every time I talk to Mom she brings up this sister. When I asked her to stop, and told her how it hurts me, she said “too bad!”

So now I let her talk and don’t respond until she is forced to change the subject. I’ll just say “uh huh” and don’t feed the topic.