I miss Her

Years ago, when we first moved here, I met one of the most amazing women I have ever known. We hit it off right away and became the best of friends. She had children close in age to my own so we found ourselves not only friends but two parents going through the same parenting issues together. We shared similar religious beliefs and had so many interests in common. We spent a lot of time together, she was family to me. She shared my tragedies, helped to pull me through them. She shared my suffering, my pain and was there to help pick me back up again. On the days I didn't want to breathe much less get out of bed, when I finally would force myself up she was there. If doing nothing more than washing my dishes, she was there. For that alone she will always be special to me. We hurt together, we laughed together, I loved her.
She was, at the time, in a marriage that was falling apart. I was there for her. When they moved away in an attempt to start over I was so sad. I knew I would miss my friend terribly. I also knew this wasn't the first time they had moved around and she didn't have much contact with old friends she had made. This was just the way she dealt with moving, it made it easier for her to move on. I knew this, and accepted that about her so I didn't expect to hear from her much. We still have occasional contact, not as much as I would like, but again, I knew this. They eventually ended up in divorce.
Her husband has moved back to this area and made contact with myself and some mutual friends. The mutual friends have been in regular contact with him since his return, I have not. They want us all to go visit him, hang out. I cant do it. I have tried and tried to turn this over in my mind but I cant do it. She was my friend, she is my friend. He was really horrible to her and if I were to go I feel as if I would be betraying her. Even though we don't have the regular contact that we did I cant do that to her. Maybe its silly, but I see it as an act of betrayal and she meant to much to me. Even with distance and time between us she is in my heart, always will be. Maybe I am faithful to a fault when it comes to my friends but I don't necessarily think that's a bad thing. Is it?