Joy is what happens when we allow ourselves to recognize how good things really are.
I believe that one reason I felt so much joy during the chemo process was that I was aware of exactly that. I saw how loved I was, and how much I loved. I had friends, family, and incredible medical care. I would go out in the world, and see people who were much worse off than I. It was a wondrous opportunity to see how good things really are, and experience the full rainbow range of joy.