It could be someone like a co-worker or the checker at the grocery store. She'll smile at first and you reciprocate and say hi. And then you don't say anything. You just do your thing, whether it's your job or load the conveyor belt, but you don't say anything and focus on what you're doing. Then you look at her and she has a shit faced look on her face. It's almost as if she's pissed that you didn't give her attention. Ever run into this type of thing?