“Happiness can be found even in the darkest of times, if one only remembers to turn on the light.” — Albus Dumbledore from Harry Potter and the Prisoner of Azkaban
Happiness should not be sought externally, because it is fleeting and can be taken away as easily as a pen stroke or another person changing their mind. It is transitory.
Internally created light is powerful, because we generate it when needed because we can, because we have the internal spark to generate the energy and power required to brighten ourselves and those around us.
Look for the light within when the world is dark, because others will need to look to you.