Changing something about your life is a valid response. So is short-circuiting the measurement system. Keep in mind that the measurement system includes external cultural/societal pressures, out-of-date instinctual responses, and your emotions as interpreted through the lens of your own emotions. A disadvantage of changing what you do, instead of how to feel about what you do, is that you will probably arrive at a place of dissatisfaction over and over again.
This. I have a friend who changes jobs about every 6-12 months chasing happiness. And every 6-12 months, I can count on him starting to bitch and moan about everything at the job. He refuses to listen to the idea that maybe happiness should be externally obtained and instead should start from within somehow. In a lot of ways, this seems to be an Eastern-Western dichotomy.
We can decide to wake up and be happy or we can decide to wake up and let something dictate our happiness. Whether we do it consciously or not, it's still a choice.