How do you cope with people who dishonour, violate, disrespect, neglect, manipulate, lie and more?

How do you cope with people who are pathologically mean? (people of ''adequate'' intelligence and ''of age'' who ''should'' know better...

How do you forgive these people?

I do not feel that it is wise to forget their actions..

(not about anyone here)

(this is not about the situation in the world and I respectfully request no posts about that)