Well, it is not physically possible to fully understand someone, as you can never know every memory and influence on someone. People are just too complex to fully understand them. I did mean something more along the lines of your description of not-wearing-masks. The only reasons I can think of for fully knowing someone, is to appreciate them and to communicate with them better. Those two factors don't necessarily require you to know everything about someone. A generous amount will do. Maybe it's better to remove the past from the equation. The full picture I seek in people is the unrestrained existence of a person. The way they act (or more literally, how they don't act but are) around me, without masks. So let me rephrase: I think I only truly know someone when they are comfortable enough to show their unmasked self, which I am familiar with. Just like you and your SO. I am grateful to have people around me who fit that criteria. Circles of friends where I can just be my true self. I feel like I have the full picture of those people, as I understand how they think because I've had plenty of conversations with their unmasked self. _refugee_, isn't that truly knowing someone? Pursuing perfectly knowing someone is futile, after all.
The not-wearing-masks bit feel more clear. I have always viewed it more of a matter of modulating one's personality to fit the appropriate occasion than necessarily wearing a mask, though. There are times you are truly wearing a mask - when you are not presenting yourself truly at all - and other times you are simply a less (something) version of you - less exuberant, less foul-mouthed, less inebriated, whatever. I think we are different people. Who I am to my parents isn't who I'd be to a partner and it doesn't necessarily have to do with wearing a mask. I certainly have friends I can be very weird around and I appreciate that and they are my favorite friends. I get that idea of "not being constrained." But who you are has as much to do with your ability to modulate your personality (otherwise you become obnoxious in the wrong situation) as who you are when you don't modulate it. Are you unable to control your emotions? Do you control them too much? Do you sometimes rage like Alec Baldwin or do you react by not reacting? I don't know. Just theories.