As an undecided young person, the only thing you can rely on are hopes of a rosy future. The things that give you strength and nourishment - parents, friends, love, dreams: these are always there in the backdrop, omnipresent life-support systems. These are the things you believe in, derive faith and hope from.
But with this comes the realization of being so vincible and vulnerable. None of these things would last forever : what would happen to my faith then? Where do I place it? Where will I get the strength to move on from?
If I had a god, my righteous steps would be lured to a heaven in waiting. There would be light at the end of the tunnel.
But the path of logic has a gripping finality to it. There will be no escape from it, no fairyland to find solace in.
Take away a rational man's dreams, inspiration, love and you'll be left with the madness of a religous fanatic who's just discovered the non-existence of god.
What is life without purpose?