Some quotes from A Confession, Leo Tolstoy:
My life came to a standstill. I could breathe, eat, drink and sleep, and I could not help doing these things; but there was no life, for there were no wishes the fulfilment of which I could consider reasonable. If I desired anything, I knew in advance that whether I satisfied my desire or not, nothing would come of it. Had a fairy come and offered to fulfil my desires I should not have known what to ask. If in moments of intoxication I felt something which, though not a wish, was a habit left by former wishes, in sober moments I knew this to be a delusion and that there was really nothing to wish for. I could not even wish to know the truth, for I guess of what it consisted. The truth was that life is meaningless.”
“Had I been like a man living in a wood from which he knows there is no exit, I could have lived; but I was like one lost in a wood who, horrified at having lost his way, rushes about wishing to find the road”
“If a man lives he believes in something. If he did not believe that one must live for something, he would not live. If he does not see and recognize the illusory nature of the finite, he believes in the finite; if he understands the illusory nature of the finite, he must believe in the infinite. Without faith he cannot live”