You needn't be. Money doesn't buy happiness. To wit, as quoted therein:
Then you feel really empty: why has that guy who is bloody useless got the same? Many can't walk away because they love the money for its own sake. So they just collect houses around the world they will rarely visit."
Actually it seems money does buy happiness.
http://www.livescience.com/othernews/050406_money_happy.html