Well, first off life is the game you only get to play once and you don't know the rules... But otherwise, the purpose is to enjoy it to the fullest. We only get a short time here.
the purpose of life is to live it to the full extent, then pass it down to the next generation. without life, there would be nothing, and space itself would just be empty gasses mixing around and nothing would exist.
Well, stuff would certainly exist without life. It's not like the planets would suddenly disappear, but I guess it's like an "If a tree falls in a forest" thing.
