Perhaps, the person who judges others harshly is trying to reject people before they reject her.
Maybe, the introverted guy who thinks that extroverts are inferior to him is still ashamed of being an introvert.
Perhaps, the person who says that having sex for pleasure is a sin is afraid of being ridiculed for his inability to enjoy pleasures.
Maybe, the person who spends hours trolling celebrities online is trying to survive in a world where “ordinary” people are not treated with respect.
Rejecting people before they reject you is a strategy to hide your feeling of worthlessness.