The people or personality we are having at the moment, is not really what we are, or rather a very small part of what we really are.
We are here in a sense to ‘experience’ things and from it ‘learn’ and ‘evolve’
which in a general sense helps in the expansion of the universe.
Each thing we experience is very unique, no two people will ever really experience the exact same thing, or have the same reactions, so in a sense it is a mass collection of data. (experiences)
The universe expands by learning through our experiences and with this knowledge it is evolving to something else or a final state.
The universe contracts and expands, or rather implodes and explodes with each ‘version’ things run a little differently.
There are also countless universes, imagine them all as spheres floating around in a void ocean.
There are things also living within this void ocean.
If we remembered whatever we experienced before we wouldn’t really be able to learn from it in the same way as we are supposed to.
Most past life memories may not even be yours, its just accessing a preexisting set of information that you align with, all information exists in the quantum backdrop of reality itself.
With this continuous learning and growing, we start refining our own complete being into something more.
Consider that we are journing on a road of experience to meet the source of the universe and become like it.
So then more universes can be created over time which then follows a similar pattern.
The memories of what we experience past and future are there, as all time already exists but we choose to make a linear progression forward, time is just perception really.
The personality of yourself can remain as a ghost as long as some driving force allows that remnant or revenant energy to not dissipate properly, like ‘unfinished business’ a need to protect loved ones or revenge for a perceived wrong.
While this already stretches’ most belief systems, I will pause here as belief is a thing people hold close and feel personally attacked when you present ideas too far away from what they believe.