If you sleep in metal armor, roll vs CON or all ability bonuses go down one. This is cumulative until a night’s rest not in armor or curing magic.
After a week, you need recreation. If you get none: -2 INT, WIS, CHA. Go to low quality place: -1. Average place, no change. Good +1 for 1 day. Places could be a tavern or a relaxing natural spot.