Yes, I totally do this too, and like you it's my conscious attempt -- which then goes too far -- to overcome, hide or mask my real feelings of social anxiety, shyness, reserve, or even mild depression where my true behavior would be more along the lines of "Leave me alone" or not even being there in that social situation, yet I feel that if I "be myself" it would be unacceptable.
That's a distorted perception on my part, but that's what I'm constantly fighting to accept, and don't quite manage to do so, hence the habitual overcompensation. It does leave me exhausted, and I also go home realizing I keep failing in my battle with this. I started doing it at its worst intensity when I went through a situation in which it vitally mattered what impression I made on people because I was at the mercy of needing help for a while during a crisis situation. I've never fully got over that, hence still doing the overcompensation when I really just feel like being reserved.
I'm trying to work on myself with this whole issue, as it does actually upset me a lot and occupy my thoughts. I need to do a kind of cognitive behavioral therapy on myself to take onboard that it really is okay to just relax and be my real self, as whatever it is I think wouldn't fly is not actually as bad as I think it is, and nobody would even notice anything but just a calm, maybe more reserved person. It's a process of self acceptance that can rid oneself of this oveercompensation, I think.
But yes, just to say, you're not alone.
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