1.) Humor is helpful. It keeps the tension below the belt, keeps the stress levels lower.
2.) Sometimes you have to treat life like a video game: It's an RPG mixed with an FPS: You run around doing quests and objectives and if you fail, you re-spawn every morning: when you wake up.
3.) Think Progressively. Instead of wondering "why" things happen, try to figure out what the lesson you're supposed to learn from the hardship is, and therein will be your answer to "why."
4.) Try, try, and try again. Failure just means that you figured out how not to make a light bulb, that's all. Eventually, you will get there.
5.) Make Self Maintenance a priority. The world has been here much longer than you have, and if you are going to carry it around, learn to stop and put the stone down and rest for a while. Just as importantly, learn when to pick it up, and get going again.