You are emotionally mature if you bring happiness to life.
CHappiness is not something which exists in the world. It is something which exists within you. Happiness is an attitude; a choice that you make. As such, you can bring happiness to any situation. Even in the direst of circumstances, you can choose to be happy. If you find this difficult to believe, think about the people of 3rd world countries. These people struggle each and every day for things which we take for granted – simple necessities such as food. Yet, they choose to be happy.
When you are emotionally mature, you understand that you can be happy while still wanting more from life. You know that your happiness does not depend on the world, that your happiness does not depend on others, or the results you achieve. You understand that your happiness is a choice which you make.