Since you mentioned anxiety over your potential reincarnation, I'm gonna set aside the physics of the question (which I certainly don't understand) and address the metaphysics (which I also don't understand, but that's kind-of my point).

There's a lot about the human soul and free will that we don't understand right now. We don't even know if these are literal things in the first place, let alone how they are connected to or influenced by the physical world.

So, let's go ahead and assume the universe is operating on an infinite cycle of big bangs and big crunches and that it never loses nor gains matter nor energy in between cycles - so, eventually, it's inevitable that a random shuffling of the matter and energy will create a physical state identical to today. Whether you (for any definition of "you") will end up back here, making the same post on a new Reddit for the same reasons, is still very much uncertain.

Let's suppose that your soul - that is, the "I" in "I think, therefore I am" - is actually something firmly bound to the physical realm, created and destroyed with your physical body. In that case, along an infinite timeline of universe renewal, there may indeed be a future instance of you who lives an identical life but that wouldn't actually be you. You would have completely creased to be at the moment of your death, and the new instance would just be an entity who happens to think and operate exactly as you did when you were alive.

Conversely, let's suppose that the soul is eternal and will eventually find its way back into an appropriate body after the one it currently inhabits has perished. Yet, for whatever reason, it carries no memories from one body to the next. (Otherwise we would clearly remember our past lives, unless this just happens to actually be everyone's first life.) In this case, we're eventually going to run into a situation where "you" will be in the same body and probably under similar starting circumstances but now we've got to address the question of "free will". Is it guaranteed that you, with no memory of this life, will make the same choices that led you to the state of mind you are in today? Even if so, since you can't remember the last time you did this, is it really still the same "you"?

I think the actual answer to the question you're really asking is more philosophical than it is astronomical, and it's one that nobody today is currently equipped to address definitively. It's certainly an interesting area to explore but, absent religious faith, until we develop science and technology that can quantify the properties of the soul, there's not much we can do but aimlessly speculate.

If there happens to be such a breakthrough in our lifetimes, I'm sure that would be interesting to learn from. Until then though, focus on enjoying the life you have now and let the next one (if there is one) worry about itself.