my best friend - I need help

So I recently fell out with my best friend, and I miss her so much. It hurts me every time I think about the good times we had. But we also had some very bad times, some very bad arguments. I didn't know how good I had it until I think about it, she was my best friend and I loved her more than anything. I'm so sad. I want to be her friend again so much,, I don't know what to do though because I know she feels the same way but it was always so mentally draining and when we fell out I had to get over our friendship and move on and it was so f*cking hard, literally! Anyway, I guess I just don't want to be friends with her again and then fall out and have to move on all over again becaus I don't think I can do it again.

I want it to be how it used to be so much, when it was just the two of us. She's my best friend in the world and all I want is to have her back like the way it used to be. But I don't know. I need help.