It's funny how much I really do for people and I never once complain or ask for anything in return I go above and beyond for people but I don't get

I do remember all of the good things that my best friend ever did for me, she was always doing nice things for me and my kids, she was priceless to me.... Until she was getting a divorce she changed, she became very a very angry person, even taking it out on me, and even though I loved her I couldn't bare up and stand against her blows, nor did I want the same thing for my own marriage.. I know I've failed her deeply, I don't know how to repair our relationship.. It's like I've abandoned her during her darkest hour... I think about the good times we had, and I miss her.