I started to read this and felt compelled to finish. I lost my mother two and a half years ago and went through a lot of the same emotions you have described. We all were with her as she died and she was where she wanted to be. In the middle with all four of her children around her.
It takes a while to process your feelings and sometimes we need help. I think writing helps sort some of those feelings out.
You have helped others with your writing today.