Not to be too cynical here fellas, but it's perfectly possible that she only appears to be happy, and could very well be unhappy. You shouldnt assume just by the image she portrays.
Also, "good things happen to good people" is pure Just World Fallacy. In reality, not only are good people not rewarded, but they're punished for being good, and bad people get rewarded.
Not saying this happens this literally in all cases, but it seems to align with reality.