Dh and I only allow ourselves, and predominantly the other one of us to moan on a Wednesday. It started as a joke when we noticed that we were spending the first half-hour after work moaning about things we either couldn't or had no intention of trying to do anything about, every single day!
We soon discovered that most of that kind of moan aren't worth remembering from Thursday until next Wednesday and that some aren't even worth holding on to from Tuesday to Wednesday. It has made life so much more pleasant NOT moaning about the weather etc. every day.
A genuine complaint can be taken up on any day of the week,