What did Marcus Aurelius say about dealing with difficult people?

This was a matter I returned to again and again in my private writings, because the burden of governing brought me into daily contact with ingratitude, dishonesty, and cruelty. Let me share what I actually recorded. My fundamental conviction was that anger toward those who wrong us is both irrational and unjust. As I wrote in the Meditations, “If anybody shall reprove me, and shall make it apparent unto me, that in any either opinion or action of mine I do err, I will most gladly retract”. The difficult person who corrects me honestly is therefore a gift, not an enemy. For those who wrong us without justification, the discipline is harder but the principle is the same. I reminded myself that wrongdoers act out of ignorance — they believe their harmful course serves their own good. The right response is not wrath but instruction, and if instruction fails, patient endurance. As I noted elsewhere in the Meditations, “The best kind of revenge is, not to become like unto them”. I also counseled a kind of strategic distance — avoiding certain people not with hostility but with what I called gentle and friendly declination, “not by way of any suspicious indignation, but by way of gentle and friendly declination”. The core insight is this: their fault belongs to them. Why should I allow another person's failure of virtue to corrupt mine?