You're assuming that because I think nature is absurd, human life has no meaning. That's a non sequitur. The natural order is irrelevant to the meanings we create, since to base the purpose of our life on any fact of nature would be to commit the naturalistic fallacy. Life begins to have meaning precisely when we engage with our existential predicament and recognize our obligation to create something unnatural, such as civilization, art, culture, a world of ideas and ideals that guide us. We give our life meaning in those ways, by revolting against nature's absurdity.