While I'm on the topic of getting old and changing your perspective on life an all those heavy topics, I thought I'd drop a link that actually shows some of the science behind this stuff.
Here is an article by the one and only Christof Koch, describing some research that he has done regarding perception and circumstance in human beings.
As much as we'd like to think that our view of the world is based off of hard evidence and objective reasoning, the truth of the matter is that what we perceive is significantly influenced by some decidedly subjective factors. Expectation, bias, personal opinion, and even your level of tiredness can change how you perceive the world around you, as witnessed in Koch's interesting experiments.
For example, in one study subjects stood at the top of a hill and were asked to judge how steep it was. One group of people stood on top of a sturdy box while doing this, and the other stood on top of a skateboard (don't worry, nobody ended up taking a plunge). Both of these objects were the same height, and yet those on top of the skateboard rated the hill significantly steeper than it actually was (the subjects on the box did not do this).
Having the experience of being on a wobbly skateboard changed their perception about the world around them, distorting it to induce more self-preserving behaviors by making them nervous.
What this suggests is that our own opinions about the world and the feelings that we have at any given moment are not completely based on the world around us, but on what we decide to be the world around us.
Given this implication, one can come up with all kinds of interesting ways we might test this theory out. At the very least, it might make us pause the next time we swear that all the red lights are conspiring against us...