No one said it's easy

No one ever said life is easy.  We all struggle with family, friends, health, life, and everything else.  It's always disappointed that when things don't go the way you expected/wanted.  I am just not sure why I can't be happy when I have things or the life that one can't complain too much about.  I live in one of the greatest places in the world, a loving family (even though we have our down times every now and then), and a rather low stress life.  Nonetheless, I still feel that it's not enough and I still want more. Is it normal or I am being too greedy?

A gorgeous rose garden