Chris A writes about Mother Theresa and asks, "Shouldn't people be self-reflective about their lives, and shouldn't we expect that self-reflection to be crushingly uncertain from time to time?" The answers are: Yes, we should expect people to be self-reflective, and yes, self-reflection should be uncertain. But no, we should not expect the uncertainty to be crushing.
Everyone, believer and skeptic alike, is uncertain—even unconvinced—about a lot of things, with no distress whatsoever. Are you absolutely certain your keys are on your dresser? Not just pretty sure, not just confident, but so absolutely certain that even if you looked at your dresser and the keys were not there, you would doubt the evidence of your senses rather than look in your pants pocket? The notion is absurd.
Everyone deals with uncertainty. We should be astonished, not blasé, that uncertainty over some ideas causes distress. This sort of distress is patent evidence of neurosis, not mental health.