Unhappiness is a dangerous thing, like carbon monoxide. You don't smell it, you don't taste it, it's formless and colourless, but it poisons slowly. It seeps into every pore of your skin until one day your heart just stops beating.
The world exists on thousands of different levels and just because some are more tragic than others, it doesn't make them any more valid. You fall into that way of thinking and you become so overwhelmed by the world's suffering, you go mad.