Happiness in those three areas is totally figurative.

1. Relationships. I'm currently single with no potential prospects and currently quite happy with it.
2. I can see how good health can affect your outlook on life. However, there are people who live with chronic pain and don't let it affect them.
3. With the income, I would have to say it's based on being able to provide for yourself and those under your care. That would be considered "success" for me. Some people need to have an excess of money in order to be happy.