Have you ever had that experience where you are introduced to someone, and then after a few minutes you realize you know them? But you quickly realize they have no idea whom you are, so you stare at them and wonder if there's something you can do to make them recognize you.
And when they say "Nice to meet you" when you're leaving, you don't know how to feel.
It's like you're trapped in someone else's body because the other person has no idea you are you.