should I contact her?

I used to be best friends with this one girl, we did everything together. But we had a falling out because turns out she slept with the guy I was dating/ sleeping with. She swore it happened before me and that guy started dating but she lied to me and it came up in conversation before so she had chances to tell me but didn't to "protect me". Her boyfriend was devastated and broke up with her because they were dating and she cheated. So our group fell apart. I tried to let it go and be friends with her but I felt I couldn't trust her so I dropped her. Shortly after I dropped her and the guy broke things off with me they started dating after swearing there was nothing between them it was a one night mistake blah blah blah. This was a few years ago and. Ow she's popping up in my dreams and I miss having her as a friend but I don't think I should reach out to her.