I would argue that perhaps you have confused happiness with joy, or I have confused happiness with a lack of sadness, or perhaps with satisfaction.

While I find that joy is a fickle and fleeting thing, I feel that I am happy most of the time, satisfied that things are as they must be, or at least close enough that the state of affairs does not poorly reflect on my efforts.

Sadness or grief make their appearance, but need not make life a poverty of happiness.

I think probably many people think that happiness and joy are the same thing, thus robbing themselves of happiness in an eternal pursuit of joy. If joy were constant, it wouldn’t be the joyful treasure that it is.