What is happiness?
No matter where you look for the definition of happiness, the definition has to do with:

"The mood of the person who is fully satisfied to have what you want or enjoy a good thing"

The primary difference between joy and happiness is that one is a state of mind and the other a state of mind. This state of mind is ephemeral, since it depends on material goods, circumstances or people who have to do with the above. If material good is damaged, if circumstances change or if someone betrays us, our mood changes and we stop being happy.