This has been something very fascinating for me. As a child, long before I ever knew the meaning of parallel universe, I used to imagine that there's another world somewhere with identical beings as that of earth only that as opposed to alternate lives, they were expressions of all our negative emotions. That started to make little meaning when I learnt about the possibility of parallel universes and multiverses. I once got into a conversation with a friend that reads "what if the light at the end of the tunnel is the light to a labour room somewhere. You come out as a new born and the only reason that you cry is because you are sad that you are leaving your life behind. As you grow, you forget your past life but sometimes you have like glitches from your past life and that's the Deja Vu we often experience." might sound weird and a little crazy right?