Nothing we do matters, cosmically speaking. However, each of us is at the center of our own universe, and from that context, a variety of things are important or unimportant. From the context of self, we derive importance. That universe exists only as long as the self exists. In that context, what you deem important is important. What you deem unimportant is unimportant. And those states shift over time. I'm not well…
> Nothing we do matters, cosmically speaking. This is true of course, however I can't imagine living thinking that and not getting depressed/insane.
[1] The backwards law suggests that if you are pursuing happiness, it makes you unhappy. If you just relax, happiness is more likely to come.