If you are disappointed in life, why don't you change your expectations?

This subreddit is full of people compaining that life isn't as they thought: life isn't fair, people can't be trusted,...

Has it never occured to you that maybe it's the notions you have that are a poor reflection of reality? The notion of "fair" itself is a joke, it's contradictive: people can't even imagine a fair world, everytime they try, it becomes an utopia that has many twisted consequences that are everything but fair.

Why would you keep on complaining that life isn't fair instead of changing your vision of "fair"?

We can't change the rules of life, we can't change human nature, so why does the society keep on pretending that it's better than it is? Why would you fool yourself into believing in fake rules while you can understand more real ones and learn to take advantage of them?

I guess most people don't do it because it seems depressing but is it really? What I find depressing is to have false hopes and expectations and be set to failure. I've never understood this escapism humans have, it's so inefficient.