We live our lives within a story. In this story, we are the protagonist. But the world is large, and our capability to act within it small. This is one story, and following this story leads to the conclusion that our actions are futile - they don't seem to make a difference to the seemingly pre-determined movement of the large universe. It is important to point out that no one individual life does seem to matter much - very very few have ever left a mark on history that is significant, and even less beneficial.
We see the world around us with the eyes we have, and those eyes don't see into the microscopic or macroscopic. But, there is a universe around us that we seem to be right in the middle of. And, there is a microscopic universe within each of us - we are each of us a universe to the tiny cells and beings within our skin. These tiny beings live within an immense and unfathomable environment in the same way we seem to live within a larger, infinite universe.
Ancient peoples thought when lightning struck or a volcano erupted that the gods - the powers of nature - might be angry with them. Is it possible that there actually is a relationship between nature and man, but not one of reward and punishment for good or bad deeds done, but a form of communication between the large and the small?
If my body is a universe for all that lives in me, then my state of mind and emotions are the climate, weather and natural disasters within that universe. I am the god of this universe, and without this universe, I would not be. God is only god when there is something to look after. The question is, what kind of god would I like to be? Do I want to reward and punish, have the earth within me open up to swallow those who displease me, or do I want to provide something perhaps...better?
In this story, even when I am absolutely alone and it seems my actions in the world are inconsequential, this is not the case. I have a universe of beings - differentiated cells within me. These beings have goals, life spans, and can be sick or healthy. What I can do for them is try to provide an environment in which they are not afraid, and are not forced to do my bidding. I will not suppress their joy with my judgement, or force their submission with threats.
The universe within you can be a universe in which these beings thrive and enjoy their time as much as possible. And maybe then the universe around you will also feel different, for the gods of this larger universe are learning from you.