It seems that the only reason to earn lots of money would be so that a person could then secure some kind of happiness. However, happiness is an outcome, it is a result, a by-product of circumstance.
What circumstances make you happy today? What will cause you to be happy twenty or thirty years from now? The answer to these questions might get you a bit closer to understanding what to pursue, where to focus your energies, and what is important to you.
I like to look at that question this way: Imagine that you have lived a long life and now you are in your 70's or 80's. You know that very soon you will die. What will make you feel that your life has been worthwhile? Will it be the million dollar bank account? Your relationship with your family? The lives of others that you have positively affected in some way?
It is interesting to put yourself in that position--just to try to project how you should live your life from here on out.