A vareity of factors go into happiness, and it isn't nearly as complex or esoteric as most people think.
-Genetics
-Good nutrition (healthy fats for brain development, certain vitamins/minerals for chemical reactions in the brain. Omega 3s, methyl donors, B vitamins, selenium, magnesium, zinc, etc)
-Cognitive dissonance and neural scaffolding (pretending to be happy activates the same brain areas as actually being happy)
-The ability to see what your life 'should' be compared to what your life 'is' and see alot of similiarity. Massive disconnects between the should and is leads to depression
-Meaningful relationships with others where you are connected and useful
Those are the 5 big factors I know of. With money or success, you just get used to it and the enjoyment goes away with time. I have researched this issue pretty thoroughly