walking alone

I have been struggling for months with this. And I have to put it out there to deal with it. One of my very best friends walked out on me last year. I need her. I have needed her ears and her understand and her laughter. We have known each other since I was 16. A VERY LONG TIME! She walked out on me. She was the only friend that I specifically called to tell when I was diagnosed with leukemia. She cried. I cried. We cried together. I wasn't alone. But that was it. There hasn't been a  close connection between us since. I know she is busy. She had recently returned to work after being a stay at home mom. She has 4 kids. Her husband is going to school and working nights. But it has been over a year since I have talked to her on the phone. I have called and text. I sent emails. No luck. She wrote me off. And of course, I blame myself. If only I hadn't called her when I was diagnosed. I know my diagnosis hurt a lot of people. I think the hurt is too much for her. I think she had to withdraw to protect herself from the pain in case I didn't make it through this journey.
I feel all sorts of emotions. I am sad that we no longer talk. I am angry because I needed her friendship. I am confused because I don't understand why she isn't here with me to support me and be there for me.
This situation has made me build up a wall that I had taken down. Friends hurt. And even though I feel that pain, I do hope that one day I will be able to trust and have a wonderful friend like her again.