Life can send you some crushing setbacks. It can send you some glorious victories, and daily between those two poles, stuff happens.
I have come to the conclusion that Life is only worthwhile if you are doing things that are significant to yourself. You have to be doing stuff on a daily basis that makes you happy and feeds something in your psyche. I have really gotten into this lately: http://buddhistbright.blogspot.com/
The circumstances around our life are so chaotic and unpredictable, that we have to control the elements in our life that we can. We have to control our negative thoughts. We have to make ourselves peaceful and calm and in doing so, we make ourselves happy.
In short, the thing that I have discovered and has been re-affirmed to me this morning, is that my Life has no meaning unless that I am happy in it. Simple, yet hard. Just like life.