I have experienced betrayal from a group that I thought would never leave my side. I just knew when the chips were down, they would be there to lift me up, to pray for me, to love me through it all. They did not. In fact, they left me and chose to spread lies about me. It hurt. It hurt badly. I longed for them to ask forgiveness, but they never did. They sat there and acted as if they were above reproach. I hurt over the betrayal for over a year, even talked to my therapist at the time about the pain. She gave great advice. Forgive them from your heart. It took a long time, but I was finally able to and move on. I still long for the closeness we had, but God replaced that group with some amazing friends that loved me through my darkest hours. They still hold me up in prayer. We have a reunion once a year if not twice. We still get together to celebrate each others accomplishments. I treasure them. I pray for them just as they do me.
So, yes, betrayal is painful, but God has something greater for you. The process of forgiveness over betrayal is hard and painful, but worth the journey.