Broken people don't hide from their monsters. Broken people let themselves be eaten.

Mais c'est renfantillage - this is childishness!' we heard de Grandin pant as we closed in and sought a chance to seize his skeleton-like antagonist. 'He who fights an imp of Satan as if he were human is a fool!'

("The Man In Crescent Terrace")

Every monster could be saved.

I knew he was a monster. It's always good to have monsters on your team.

The reason Armand Gamache could go there was because it wasn't totally foreign to him. He knew it because he’d seen his own burned terrain, he’d walked off the familiar and comfortable path inside his own head and heart and seen what festered in the dark. And one day Jean Guy Beauvoir would look at his own monsters, and then be able to recognize others. And maybe this was the day and this was the case. He hoped so.

Whoever battles with monsters had better see that it does not turn him into a monster. And if you gaze long into an abyss, the abyss will gaze back into you.