The king of Nihilism, Nietzsche, believed in "the will to power", similarly the father of existentialism, Kierkegard, believed in "Eithe/Or" that you will suffer no matter what, whether you are lonely you will suffer or if you aren't lonely you will suffer, but so long as he was the one feeling that pain it was his to possess.
Nihilism is rooted in Nietzsche's philosophy, and Nietzsche was inspired by Schopenhauer's "World as will and representation", keep in mind that these two figures did not believe in God. Schopenhauer believed in a blind dumb will that was forever striving, and its only purpose was self-preservation and pro-creation (sex) and beyond this was nothingness for life... Nietzsche borrowed Schopenhauer's philosophy and dubbed this as Nihilism, and furthered the so called dumb blind will and gave it purpose, which he referred to as "The will to power".
Just remember... Allah in the Quran said... "And I did not create the jinn and mankind except to worship Me."-Quran 51:56 So Nihilism is correct that life is meaningless, and it is very much so if you take away God from the equation, that is the ultimate choice you have to make for yourself.
There is nothing optimistic about nihilism, in the absence of God, the universe is just purposeless collection of atoms in motion. So why even bother to indulge in the pointless exercise of creating subjective meaning for your existence, when all your actions lead to meaningless manipulation of atoms?
Ahh... Don't patronise, perhaps he's still learning.
