re: Looking back at times where you missed out on an obvious opportunity for sex

I met this lady (she might have been a little older) in biology class. From what I remember it was halfway through the semester and I’ve never had seen her before.
She’s making small talk etc. after class she needs a ride to her room at a house she’s renting. She invites me inside. Offers me water or coke. We talk for a few minutes and I leave to go to work. I never saw her in class again. Wtf.
I have had a few recently that have pulled me aside at networking events to tell me that they are recently divorced or have broken up with their boyfriend. I’m married. But I don’t know if these confessions mean anything.