What? Yes. I know it's hard to soak in that statement. Trust me, you have learned invaluable lessons from these people.  In the words of my favorite wisdom teacher, Eknath Easwaran, these so-called “difficult people” gave you "an opportunity for learning the skills in life that matter the most: patience, forgiveness, and freedom from likes and dislikes. When the mystics of old think of someone who has been a thorn  in their flesh, they will say to themselves, 'Without you, how could I ever have learned to be patient? How could I ever have learned to forgive?' "