Masking: Coping Mechanism or Self-Destructive Behavior?

It feels so complex and almost innate now because I've done it so much. The more exhausted I am, the more deliberate it becomes though. I smile, nod, think intensely about what the other person is saying so I can relate and respond, etc. I have some phrases that I use a lot like "oh yeah" "oh sure." "Makes sense" "I see" "that's interesting/funny". Sometimes using those phrases gets me in trouble if I didn't correctly guess the emotion of the person or spoke before I fully analyzed what they said, ex. Them: "My dog died. We burried him yesterday" Me: "oh sure, makes sense" I usually notice quickly that that wasn't the right response based on the person's response and scramble to get it right ("oh uh um I'm so sorry! That's so sad! How old was he?") When I'm really drained, I can't maintain my face and body posture normally and I just look pissed off. I can put it on again quickly, but that is definitely when it feels most like a true "mask". Otherwise the mask jas just become my normal :/

I work in an environment where people knowing I’m autistic would be bad so I spend a lot of time watching how people talk to each other, what they talk about, how they act, etc. and I avoid people knowing very much about me.

I try to copy someone's stance. For example: If they're leaning against something, then I'll lean against something to look more "normal" to people lol