When you complain about something—the weather, your boss, your job—anything, your listener naturally copies your dejected expression in sympathy. And whatever anyone’s face expresses, affects their emotions. Therefore, your grumbling about something makes them sincerely unhappy—and they connect that unhappiness with you. People don’t like to be unhappy (duh) so they’ll start avoiding you.
Take it a day at a time Don’t let one complaint slip through your lips tomorrow. In fact, start right now. Then try to extend the moratorium on complaining another day . . . and another . . . and another.