For very understandable reasons, we spend an enormous amount of energy trying to make sure that we come across to other people as sane, balanced and normal.
We know the reality is a little more complicated but — for much of our lives — we're able to keep matters more or less under wraps.
There may have been a few extreme moments on our own in the bedroom or bathroom or driving in the car or coming home late on a train, but generally we'll have drawn tight boundaries around the crises, and no one will have known.
But then — if we are unlucky and probably if we are just human — life will test us more than this.
At some stage, we'll end up in a situation that blows apart our normal abilities to cope, which destroys our capacity for perspective, for reason, for calm and for mastery.
It might be something at work or in our relationships, a financial or a health issue, something to do with reputation or with family responsibility.
As the problem continues to grow, we will realise that we are in uncharted waters, that we are entirely overwhelmed — and that we don't know whom to turn to.
Sadly, it isn't uncommon that our thoughts may eventually grow very dark indeed.
In our private agony, we may start to imagine that it really would be better if we didn't exist and that there might be only one way to stop the pain.
If we are to survive (and there truly may be nothing less at stake), we are going to need to be very brave indeed.
