My wife had to explain to me that a girl I went to college with was into me years after the fact. She stumbled across some pictures I had on Facebook that this girl had liked and commented on and asked me about her. At the time I didn't think anything of it but she was interacting with old posts from long before we'd even met at school.

My wife actually facepalmed when I told her this one story in particular. I was in the Commons on campus suffering from a pretty bad migraine. I'd been there for like an hour when she came in and sat next to me and asked me what was wrong. I told her and she sat next to me petting my head until she had to leave to go to her next class.