Everyday narcissism

A sign of common, maybe even a normal level of narcissism, is certainly when people think their burden is The Heaviest. Why do so many people insist in making it clear that their work and their problems are worse compared to yours? A realistic comparison would in most cases show that the only difference is that one of the burdens is carried by them, and that is the only reason why they think it is objectively heavier than mine or yours.