The limital space between not being and being was an insufferable moment that no soul would wish to bear. Overring in a state of being while not being. Like the cat of Schrödinger, trapped into a box where it state was constantly redefining itself.
Voldemort.
The Madman.
Tom Marvolo Riddle.
He-Who-Must-Not-Be-Named.
In this space it was and , at the same time, wasn't all it had been once. It didn't have to think, didn't have the capacity to do so, since it was only soul and no mind. The soul remembers, the soul bears the history of the mind, never forgetting anything.
It remembers Voldemort, it remembers every single being it had been before it was him. The soul had been scattered by itself, by the mind and now, lost in Limbo, in the cold dark void of Death's Garden, the soul was suffering.
The pain of the soul was not one for the body. Since the soul and the body were on different planes, one cannot describe the suffering of the soul in terms of physical pain. But it, when it was him, had seven times bore a pain akin to the one it was bearing now. When it, while it had last being, had destroyed itself, consciously tearing itself in pieces. Butchering itself, offering itself to an eternal state of pain, because of the mind's foolishness.
Never again , shall it be reborn, the soul will forget such stupidity. What happened had being branded into the soul and will never fade.
The pain it was bearing in this eternal time of Limbo was by far superior to the pain it had bore when it had been divided. But it knew that the pain was necessary, has the pain was not here as a punishment but has a healing. To be reborn, the soul knew that it needed to be whole again, thus its parts were stitching themselves back to how they were before.
This might have taken thousands of years, for all that it knew as time in Limbo was on another scale. But how much it wanted the process to be over, it was still not whole. A tiny, little piece of itself was missing. Not here in Limbo, or it would be whole again. No, the piece was on another soul, a part of itself had merged with another soul. The soul that had been, or is still, Harry Potter.
Then, when it was almost whole but not quite, Death when to it.
Limbo parted to show a raw of darkness, darker than the void, and the reality of the being imprinted itself into the soul.
" Thou shalt find the one foreordained for thee, for thou art but half.
Thou shalt seek the one who hath been touched by Death.
Only then shalt thou be made whole once more."