22 years old. Blind date set up by a friend who was asked by the guy to "set us up". Apparently, he had heard about me from someone else and thought I'd be fun to get to know, but he was shy and didn't want to ask me himself. OK ... cool. Word of mouth is always a good thing.
Keep in mind that this was in the days before cellphones, digital cameras and e-mail, so it's not like people could Google each other or check for info online.
I get to the appointed place with the appointed "signal" (green scarf). Guy comes in and starts looking around. He's dressed the way my date was supposed to be dressed, so I watch him look around the diner. Small place (only 14 tables), so it's not like he could have missed me. He goes outside, then comes back inside, and I finally catch his attention. He looks at me and is very confused. I ask, "Are you John >not his real name<". He is even more confused and says yes. I smile and introduce myself. He turns BEET RED.
Now ... I have a name that is one of those "could be a girl / could be a guy" names. But I will admit it leans more towards a "guy" name. And ... you guessed it. "John" was gay. He'd heard about me from a mutual female friend and just assumed she was talking about another gay guy, so he asked her to set us up. She never came right out and told him that I was a girl, since it didn't occur to her that he wouldn't know that. It just never came up.
So ... there we are ... me waiting for my blind date, him expecting a guy. He was all, "Oh my god, there's been a big mistake..." and he took off -- running! I thought, "could I really be that repulsive?" I was upset and angry and humiliated until I got back to the dorm and talked to my friend and she figured it all out. SHE laughed hysterically. Not so much me. Years later, it was a funny story to tell, but at the time ... ?