I found that when I stopped making any conceptual distinction between happiness and sadness, I became fulfilled.
But when I separated the 'state' of happiness from the natural field of awakened space which also contains the poignant sorrows of the world, the 'happiness' became quite brittle and superficial.
I don't recognize 'happiness' as anything real anymore. It is like trying to separate the air in a sea bubble from the salt water. Peace.