Hello Almostheavenwv & welcome
I think that you have received some good advice here.
In my Mum's words, your children are your children, no matter how old they are, so, if she is a good loving Mum and Grandma,then they are going to come first on her list.
Maybe you can become equal first ~ but only if you can accept this. Hopefully you and she will be able to feel comfortable with you joining in more.
Good luck!