From a foundational perspective, life is only meant to survive. Sometimes not even that though. Look at the fruit fly. Whether or not one enjoys their life is irrelevant to this directive.
Do you think the wolf enjoy its life? Does a mouse?
So if we move past the evolutionary and into the physiological, were we created to enjoy life? Looking at the world, even if there is some magical god in the sky, enjoyment seems to be on a low list of things we are supposed to do.
So the question really becomes, do YOU want to enjoy your life? If so, why arent you?