Grieving over a friend loss for 27 years

Hi:
I am here today because I realize that I have been grieving the loss of a friendship from childhood for many years.   The big picture is that I was hoping that she and I would be lifelong friends only to be let down by her.   This was by hurting, betraying, and abandoning me when she met her first boyfriend and entered middle school at age 12.   Though we went through a few periods of not speaking to each other and then reconnecting,  she and her mother continued to be toxic friends.

Years later, I tried to bargain with her by attempting to ask her why she treated me as badly as she did.  Still, she blew me off and jerked me around which led me to work through three years of anger.

Today:

I have not talked to her in 13 years and I didn't hit the depression stage with her but I am working through the anger piece.    Yet, as I have recently been working through this with my counselor, I have started to come to a place of acceptance.