I never complain.

There is a useful distinction between complaining and naming a problem. Complaining circles the same grievance without asking for anything. Naming it says the tap has been dripping for a month and I would like us to fix it.

The first leaks out over years and wears everyone down. The second is over in a sentence.

The aim isn't silence. It is conversion: taking the thing you were going to mutter about for a week and turning it into one clear request, delivered once.

If you are carrying a low-grade grumble right now, try saying it plainly to the person who can do something about it.