To me, it sounds like some sort of obsessive compulsive disorder that developed to keep one's mind off of more distressing things. Things like walking, talking, sleeping (or rather staying awake), and eating have become like a ritual, routine, and are taken up to eleven by doing them excessively. The constant repetition of doing these things is executed because it reduces the "silences waiting behind the chair" that "eat anything that moves"- aka, it makes the person doing these actions feel less lonley and like there's more of a purpose. But at the same time, behaving this way is hurting the ones the narrator loves ("I hate to see your pain, but I don't know how to stop"). It's become a major problem.
To me, it sounds like some sort of obsessive compulsive disorder that developed to keep one's mind off of more distressing things. Things like walking, talking, sleeping (or rather staying awake), and eating have become like a ritual, routine, and are taken up to eleven by doing them excessively. The constant repetition of doing these things is executed because it reduces the "silences waiting behind the chair" that "eat anything that moves"- aka, it makes the person doing these actions feel less lonley and like there's more of a purpose. But at the same time, behaving this way is hurting the ones the narrator loves ("I hate to see your pain, but I don't know how to stop"). It's become a major problem.