Infinite parallel universes

I'm not a religious person. I'm agnostic and look at religion and spiritualism from very far, as a curiosity in the humanities.

That said, one thing I believe is more likely than not is the infinite parallel universe theory. The theory that there's an unending amount of parallel universes which contain a lot of the possible states of the universe at all times.

Now i don't believe they necessarily have to contain every state. An infinite set of numbers does not have to contain every number, after all.

However as I'm sitting in a hospital bed after the second worst near death experience in my life, I'm reminded of that theory.

I remember that theory whenever I look at the world and think "huh, I could have died there". A slip in the shower, a small electric shock, a car coming too close. I didn't die, but in very slightly different circumstances I could have. When these things happen I think of my life, my friends, my mom. I especially think about the versions of them in the parallel universes I believe exist.

I make a lot of choices based on this. It's a type of fatalism: I'm not so much worried about death here, as I am afraid about the consequences of it in the universes it does happen.

In other words, I often get sad for the parallel universe versions of my mom. there's a lot of problems with this overall theory, but I can't quite shake it.