Quite often we fear death we forget that we indeed have a soul and a spirit the one thing I have truly learned is that the human body is merely a vessel carrying the soul on a journey.
Reincarnation is in my eyes believable as is past lives lived in any form animal or human, there is no limitation on how long the soul lives as there is no physical state to it unlike the human body, our soul may have lived a thousand years before it found our body to continue its journey.
Just remember next time you question your past life and your current life their most likely a reflection of your souls previous journey as well.
So be kind to yourself be kind to your soul and the vessel your body.
Peace love light