Hi there
Rainshine...welcome

I do know how hard it was for you to write...
"I don't think I will ever have a loving mother-daughter relationship"...because I have said the same words. When you start to realize that the dream you had will not come true, reality sets in. That is not so bad because now you can start to work on what you have rather than what you don't have.
Good to read that you are being pro-active...you have a counsellor

and you are doing your research in reading "Stop Walking on Eggshells." For sure that is an excellent book...and there are more. Coming here is definitely a step in the right direction. It is so difficult to deal with things if one feels they are alone. There are many of us parents who are experiencing similar problems.
I, too, am a Grandmother who has agonized over the trauma to my grandchildren as their mother (my daughter) stumbled through life. We so want better for them. I hope you will be able to continue on with the care of your granddaughter...be an alternative role model for her.
Participating in this forum a few years back was a game-changer for me. Things have not turned out anywhere near what I would have wanted them to...but...I am learning to accept what is...IS...then I do my best to deal with the reality...move on. I hope this will be the same for you. You need this for you but you also need this for your granddaughter.
Keep posting, Rainshine. Pour out your heart and your hurts. There will always be someone to respond to tell you that you are being heard...bolster you to make changes that only you can make.
From one Grandmother to another...a ((HUG)

Huat