I remember a story (possibly an anecdote or parable within a larger work, a la The Grand Inquisitor) about a person who goes about their life in an intentionally unpleasant way so that they can remain aware of every moment. The example I remember was of them choosing to taking a long, boring route to a given destionation where a shorter one would have sufficed and a more scenic one would have allowed them to be distracted on the journey.
I mentioned the story to my brother and he said it sounded familiar, but we couldn't pinpoint where from. I thought it might have been from Molloy or something by Camus, but I know my brother hasn't read the former and I've had no luck tracking it down in any of the latter.