Always keep in mind the ugly side of the other person, and don't be soft-hearted because of a few kind words, otherwise you deserve everything you suffer. When others don't respect you, you have to leave decisively. The last thing adults should do is forgive the past when they are happy. The good side may be pretending, but the bad side is real. The biggest ugliness of human nature is to please you in every possible way when you need it, and to turn your face ruthlessly when you don't need it