…questioning the existence of God may begin because of one’s sense of disappointment rather than because of a line of reasoning. Disappointment can bring disillusionment, and disillusionment can get quite a grip on us. It may be the case that, next to the grip of disillusionment, whatever reasons we can think of to believe that God exists or that God is good will appear weak. So sometimes the reason we do not believe or the reason we stop believing is not the intellectual challenge to believing in God. Sometimes, the grip of disillusionment cannot be matched by things that seem to be only abstract or theoretical.
Gregory E. Ganssle, Thinking about God: First Steps in Philosophy