Science fiction short story where one planet maintains control of another by elevating some people to power on the subject planet. These elevated people have hereditary obsessive compulsive disorder which sets them apart from the common people and also disables them from actually leading their people who are then subjected to producing for the benefit of the alien overlords. The main character’s obsession is to follow a wood grain pattern. It takes her all day and she is exhausted from it. Somehow she meets a commoner and discovers that she might live a different life. I’ve tried very hard to find the story but no luck so far.