Further to Rev. L. G. King's post "RECENT FRONT-PAGE NEWS ABOUT MOTHER TERESA'S LOST OF FAITH" (#23273 - 2007-08-27, above)

Rev: "THE CAUSE OF MOTHER TERESA'S DESPAIR WAS A BAD THEOLOGY"

Quite possibly - or perhaps it was melancholia (endogenous depression), which doesn't appear to require any external trigger. That's certainly enough to take the joy out of life, faith or no faith.

Here's an article by Sam Harris that includes related comments:
http://newsweek.washingtonpost.com/onfaith/sam_harris/2007/08/the_sacrifice_of_reason.html

"Time is what prevents everything from happening at once" - John Wheeler