Being at a party is like being exposed to an onslaught of stimuli that your brain wants to process right this minute—because, when you’re self-aware, you’re not just acutely aware of yourself, you're also acutely aware of everyone else.
That person feels left out. This person is sad. That person is angry at this other person. Can you ever just attend a get-together without leaving it feeling completely depleted? Probably not.