Happiness within your control

I had Ben and Jerry's ice-cream with my friends yesterday. It was a heart-to-heart talk with these 3 friends of mine. In one of the conversations, it was asked, what is 1 thing that would me happy in the upcoming week?

My friend answered, "Going back on time from work". She further elaborated, "That means leaving by 6pm everyday". I then asked if that is within her control. She replied that it's not. That has to be dependent on the amount of work she has, the post-work events she had to attend and her superiors.

If going back on time will make her happy and that is not within her control, happiness will come as a random event. Her personal happiness is subjected to fate and god's will. Happiness must be within one's control, else doing everything possible might end up being a futile effort.