It's not easy to put yourself in someone else's shoes. And it's even harder to do when you're interacting with them and you have beliefs, expectations, and hopes.
There's a girl I find attractive (although she's not available). And when she and I interact, it's always a thrill. Well, for me, anyway. If I replay my emotions, I'm higher than a kite, anticipating the possibilities. But, if I replay the scene stripped of my emotions, it's easy to see that she's just being nice, neighborly. Although there's a smile on her lips, there's nothing in her eyes.