Depression Support Group
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Actually what you describe is part of the actual classic definition being an introvert.
"Contrary to what most people think, an introvert is not simply a person who is shy. . . . Basically, an introvert is a person who is energized by being alone and whose energy is drained by being around other people."
So true. While I always find crowded places intensely unpleasant and that seems quite sensible to me. (Noise, emotions, sweat, odor, coordinating yourself around others). This also explains why I (and other introverts) am totally exhausted and often grouchy after spending hours with my family and friends--even if I enjoyed myself the whole time.