^If someone is unhappy with you and you don't know why, what is
   the proper response? If you can find out and fix it, do so. But
   if not: Allow them to be unhappy. Let them feel what they feel.
   But do not allow it to change how you feel. Their unhappiness
   may pass. Their unhappiness may remain. It's not your problem,
   it is theirs. Find other things to make you happy instead.
   Distraction is the key to happiness.^