Before I'm Gone

It has been years since the last time she saw another human. Years since she has been alone, all alone in her big city. Trying to keep her sanity, and keep surviving, with the only purpose of recording what has happened and tell the story, because no one else can. She has to, because she is the only human left alive on planet Earth.
She has to keep humanity alive in memory, hope that some other species in another era will rise, and learn about them; how smart they were, how beautiful, how kind, how creative. But also how cruel, how evil, how selfish, how violent, and how stupid they could be.
She hoped her journals and records would keep humanity from being forgotten and fading away.
She hoped the next ones on Earth would learn from humanity's mistakes, unlike humans themselves.

This is the story of Marie Anderson and how humanity fell and became extinct. How she became a hero to be remembered for her bravery.
But it is also a warning.
Don't do the same things they did.