Complaining is a very deadly thing. It is the habit of complaining that is at the root of various social problems. When several people live together, it is but natural that they will have differences, which are often then allowed to turn into complaints against each other. These soon get transformed into enmity, abuse and a never-ending cycle of hatred.
The only solution to complaints is not to take them seriously. Instead, they should simply be forgotten. In the event of a complaint against someone, there’s no need for you to investigate it or to remember it. Instead, you must forget it—and you should do this on a unilateral basis. It is natural for complaints to arise when living together with others. But the solution to the problem of complaints is not that you should go about trying to verify them in a bid to solve them.
In this world, it is simply impossible to stop complaints. The only practical thing that you can do in this regard is to not store in your mind any complaints you might have against others. This is the only solution to the problem. From the practical point of view, there is no other solution. If you want to live in this world with a positive mind, and also to leave this world with a positive mind, you really have no realistic option but this.
Complaints are always a serious matter. That is why the only practical solution to the problem of complaints is not to make them a subject of discussion and debate. Instead, you should think that the only way to solve them is to forget them, not to find out if they are true or false.
Experience suggests that investigations never put an end to complaints. In fact, they often only further complicate them. Given this, forgetting complaints is the only practical way to solve them.
Source: Leading A Spiritual Life