I know that life can be extremely challenging; however, ultimately, life is meant to be enjoyed. We only have a short time to experience this incredible world and the many gifts ki has to share.
Beings of Symbiosis
I think the real question is “What is OUR reason for existence?” Every aspect of Nature has a role, a purpose. We have learned this the hard way, by removing unwanted Beings (like Wolves) and seeing how greatly this changed the wellbeing of an ecosystem. Nature does not waste. Since we are, whether we realize it or not, part of Nature, this means that we too are here for a reason.