I'd rather have animals have a good life than the continuation of human populace
What makes you feel this way about humans?
My grandmother was in a concentration camp in Nazi Germany, my grandfather in a forced labor in Mao's china. Humans are despicable.
I know you feel angry about those times in your grandparents life, but you are also human. You should work to see the good in humanity as well.
If that is how it is then so be it.
That is not the way you should be thinking about things. Your life is worth more than what you are saying now. The same for your grandparents.