I have thought about this many times and up until I cut out my mother from my life. How will I feel when she dies? I feel like she already has in my life but I do wonder if I will feel like you. It all hits so differently. I think maybe because you always yearned for that relationship and those memories that were never made. They are our parents so of course we will be sad about a shitty relationship.
You have learned so much about yourself in this process and grief doesn't magically disappear although I would love it to. <3