What is the saddest truth of life?

Perhaps the saddest truth of life is that we are probably alone in the Universe.

That there exist fundamental inequalities of advantage that can never be *accurately* corrected, only generally compensated at best.

Most of these comments are about death, yeah it happens to all of us mortals but we all already know that. It's almost not even sad anymore to so many people out there. Although we may hate that they're gone cause we won't see them again, we aren't gonna die of a broken heart over it any time soon. Y'all know what I'm talking about don't lie.