What do you do? Either you suppress the thoughts/feelings/emotions or hide them.
While too much suppression leads to mental health problems and frustration, expressing it all out may lead to more enemies or a strained environment or awkwardness or whatever else.
Depending on your environment, your attitude and a lot of other things combined determines how much you are at liberty to express yourself.
As much as it is always good to express, you can't. So how much and what do you suppress and hide? What compels you to stop from saying out what you want to?