If somebody has really done something wrong towards us, what should we do?
When someone does something bad to you, think, why would they do it?
One reason could be that they are not healthy.
Do you see a fool or a mentally ill person as a culprit? No!
If a mentally ill person says something bad to you, do you take their words seriously? No. You just move on knowing that he is mentally ill.
So, when someone says something bad to you, think of it in the same way. When a disturbed person says something bad, why should you feel disturbed?