There is something about your life that someone else dreams of possessing.
This could be the salary at your job, the house where you live, the spouse with which you spend your life, possibly your toys, and even the friends in your life. There is an endless list of things people could and do covet about your life that you simply take for granted.
The biggest key to a happy life is not obtaining more. Instead, it is appreciating the things you already have.
I know God has blessed you in some way that you have overlooked. Joy is a state of mind, not a destination where we hope to one day arrive.