By the time you are 5, living with a narcissist seems normal.
The nitpicking, tearing down they do is "because they care".

Perfection seems to be reachable, and then you won't be criticized, you will get the praise you desire.
If only you could be a little bit better.

Of course, that's a lie. They nitpick to nitpick. And it has nothing to do with what you have done.
They will nitpick a guy for getting his shoes wet while walking on water.
"How dare you wear those muddy shoes inside!"

And remember boys and girls, a narcissist is working on plans to tear you down.
Not just thinking of them idly. Most of their brain power is used thinking these through.