It is impossible to describe insomnia to people who are sound sleepers. These are the people who trust that getting in bed will be followed by falling asleep, as surely as night follows day; these are the fearless people. Sleepless people are a very different breed. They know what insomnia really is: not just the failure to fall asleep, but the fear of that failure. For an insomniac, there is no such thing as a good night. Every evening – even if it eventually, mercifully comes to an end – is shredded by anxiety. To reach sleep the insomniac must first pass through terror.
The fearless person also fails to understand how easy it is to become one of the sleepless people. All it takes is one bad night. That bad night begets others: once you know you might not be able to sleep, you can't. Recognizing that staying awake all night is a very real possibility, something that could actually happen, is no different than realizing that your boyfriend might no longer be interested in you, or that the friendship you thought was indestructible is, in fact, as vulnerable as anything else, or that you could very well not succeed at doing the work you so badly want to do. When you imagine such scenarios, you seem almost to will them into existence. To see the abyss is to take the first step towards it. What made F. Scott Fitzgerald “sleep-conscious,” as he called it, was a mosquito: the bug bothered him all night, and after that he had trouble sleeping for years.