Look for Happiness and not for sadness. In life, we come across both situations : happy and sad. But generally it happens that we cling on to negative feelings more. and we hardly remember or cherish happy moments.
The game is designed on the similar concept where both happy and sadness will come into your life, and you have to choose happiness. If we condition our mind to be happy i.e. choosing happiness and letting go of sadness, our life will be much more joyful. And once the good habit of being happy is cultivated, it will be our nature.