It is human nature to complain. A certain amount of venting is good. It releases some pressure and stress. It can help us put things into perspective. (Have you ever caught yourself complaining and realized how absurd it could sound to someone who is much worse off than you are? I have.)
Complaining can also prompt us to take action and change things.
After a time, however, complaining does not do any good. Alone, it does not fix anything; it does not change anything. It just takes a great deal of our time and energy that could be used for better purposes. Do you know anyone who has been complaining about the same (probably petty) grievance for years? What a waste!
There is a sign I saw that I really liked. It went something like this: “Pull on your big girl panties and deal with it!”
There comes a point when additional complaining is senseless. Either take action and do something, or let it go. Put your time and effort into something that will achieve positive results.