The Multiverse
In one reality, you are a rock star. In one universe, you are a lottery winner and live a life of comfort. In yet another dimension, you are the Bill Gates of that cosmos.
Have you ever noticed that when people talk about The Multiverse, they always describe the best possible outcome for themselves and everybody else? Everybody is some world leader, sex symbol, sports hero, or some rich bastard in charge of everything. Nobody is some bum on a street corner shoving a needle in their arm. Nobody is a woman on a doctor's operating table getting a brain tumor removed. Nobody dreams up a multiverse where they never existed.
This is because: “wouldn't it be nice if my life were better?” The world is full of losers trying to cope with their miserable lives. What better way to delude yourself than to dream up alternate realities where you aren't some unfortunate slob, being ground down by daily life?
This is why The Multiverse and the Multiverse theory is horseshit.