Why do I dream about her 20 years later?

Been having dreams nearly every night about a former girlfriend. We broke up bitterly 20 years ago. She gave back the ring. Yet, I keep dreaming of her lately. Not ual. Just talking. Hanging out. I'm happy with my marriage, by the way, and my life. Overworked and underpaid like most of us, but overall, very happy. So, why would I keep dreaming about someone who hurt me so? This happened years ago. Four straight nights of dreams of her. I later found out that she got married that week. Was she reaching out to me then? Is she somehow reaching out to me via my dreams? Should I contact her and ask if all is well? So confused. The mind is powerful thing. Any comments or insight are welcome. Thanks.