And what makes us so crazy? (See previous post). Well, I'd venture two things primarily drive us completely nuts.
1. We know we are going to die. We don't want to die. For some wacky reason, we think we want to live forever. Stay young and live forever. We kind of hope death will overlook us. This is impossible and life is always reminding us that this is impossible. And probably not even good for us. So we live with the irrational hope and the rational reality. And it makes us nuts.
2. We think we are the center of the universe. I mean, again, it's obvious we are not, but we want to be the center of the universe. And we want everyone to worry about us, and make love to us, and care about us, and well, think of us as essential. And again, life kind of puts the lie to this idea. We are not the center, not even close, we are just beings, lucky to be alive for a short time (a blink of the eye) in the grand scheme of things. So again we live with the irrational hope and the rational reality and it makes us crazy...
At least that's my theory this morning. You can find much more in the literature from Freud and Jung. They have lots of cool ideas about all of this too!