Where does much of the world's sorrow come from?

sorrow comes from yourself when you're missing something from life, when you fear that you'll never amount to anything, or that your talents aren't enough. it happens when undeserving people receive, and you work and work, and really put your heart into it, but never get anything... never feeling like you've achieve at something. sorrow can come from the sum of the small things, that eventually add up to an overwhelming misery and stress. sorrow can come from your knowledge of knowing that you're truly alone out there and no one's looking out for you or cares if you achieve the things you want out of life. sorrow comes from nostalgia, because things used to be so simple and carefree, but life will never be that simple again. it comes from not knowing where you're going in life, and not knowing what you'll do after you get there. its from stuffing all your troubles, any negativity or anger, all the bad stuff that other's Dealt you, all of it inside... and you stuff it inside and bottle it up until you know if you put anymore of your problems inside of you, you'll brake... you truly won't know what to do.. that's where sorrow comes from