Chronically lonely flies overeat and lose sleep
So I googled "the social life of flies" and found:https://phys.org/news/2018-03-social-life-humble-fruit-revol...Humans aren't the only species with a well-developed drinking culture. The social life of the humble fruit fly also revolves around alcohol.Their favorite food, rotting fruit, ferments into a beer-strength quaff. Courtship often involves swarming boozy locales and getting frisky after imbibing. Flies also use alcohol as a palliative, taking to drink after repeated sexual rejection. And like humans, flies develop "drinking problems."