Happiness includes, even in its etymology, an element of luck. It just 'happens'. It is by definition random and transient. I wouldn't rely on it.
I've once heard someone say that you're happy the moment you choose to be. I thought there was some merit in that statement.
What do you mean? How is happiness a choice? If everything in your life is upside down how can you be happy?
Haven't you ever wondered why happiness and the greatest joy can be found among the most hopeless of people and the greatest sadness and depression among those who are universally considered to be protégées of fortune and who appear to possess everything one could desire?
Happiness, I think, is not the absence of hardships or setback, but the way you handle them. Were the absence of hardships the requirement for happiness nobody alive would be happy, since hardships are unavoidable and indeed a fact of life. To a great extent happiness and equanimity are synonyms.
At least, that's what I believe.