Well, this happened to me, but not in real time! A long time ago, when I first got a Facebook account, a friend from high school got into contact with me. He was a guy I played basketball with everyday, and since he was younger than me, I really missed him when I moved. He was just so cool. But totally just friends.
Well, he confessed to never have "gotten over me" because he was so in love with me in high school. It was a shocker because I felt only friendship and never got any other vibe from him.