Ego. It’s not all about you. In fact, it may well be that the extent to which you are unhappy with your life is precisely the extent to which you are self-preoccupied. Nobody ever said life was going to be perfect, and we all have ups and downs. If you seem to be having more downs than ups lately, find someone who needs someone to chat with once a week or so. When you chat with them really listen to what they are saying. It will change your perspective.