I don't know why, but this thread is reminding me of a situation from a few years ago. My best friend in elementary school turned against me and uniting the whole class against me and my other two friends. It was a really horrible time with everyone doing awful things and excluding us. A few years ago, she got in touch with me and we met up. I thought she was going to apologize. Instead I found out that she runs a national anti-bullying organization. I couldn't believe it!
Anyway, it's hard not to feel some satisfaction when you see someone being treated badly when they treated others badly. I doubt they recognize their own behavior reflected back at them.