I've had three long-term female housemates who weren't related to me by blood. The central problem to these arrangements, including the unfortunate souls who co-habit with their girlfriends, is that men and women are evolutionarily designed for different levels of social interaction: men for big-group stuff, including altruistic acts that benefit a large number of strangers, and women for small-group stuff, typically themselves and their immediate family. I won't review the literature, but if it interests you, the social psychologist Roy Baumeister covered the main results in his talk to the American Psychological Association, titled "Is There Anything Good About Men?"
This fundamental rift between male and female brains colors all of the interactions between housemates, the most salient and motherfucking annoying of which is that the females rarely pitch in to do housework. Oh sure, they keep their rooms, cars, and bathroom shelf immaculate -- that's the small-group focus showing up. But taking out the house's garbage, doing the dishes, sweeping the floor or cleaning countertops, or worst of all cleaning the bathroom, you can just forget about. Forget it too if common-use supplies need to be bought. They maintain a full stock of organic toothpaste, a cornucopia of moisturizers, and eco-friendly laundry detergent jugs for themselves, but they will rarely buy dishwasher detergent, plastic bags and aluminum foil, or lightbulbs. All of this they expect to magically materialize from their daddy replacements.
Lecturing them or bringing it to their attention is no help. That only treats a single symptom. Right afterward, they regress to their instinctual disregard for the group's welfare. You also risk creating a house war if you're too stern and your female housemates too emotionally touchy, which is very likely.
I don't wish to be too hard on women -- again, if they're designed to act that way, there must be a reason, and it is this: until very recently, highly migratory patterns and mixed-sex cohabitation among total strangers was not the norm. She lived with blood relatives or a spouse. In that traditional setting, she is providing her husband with children, the ultimate evolutionary pay-off, so it's fine if she doesn't go around helping strangers. However, female housemates are not providing their male housemates with anything of value, unless they're unusually attractive and give the guys something nice to look at. But such women understandably would never want to live with males anyway, for fear of being leered at all day.
Perhaps the best thing to do is create a formal schedule of household responsibilities that people rotate through, just to make sure the women contribute their fair share to collective goods. But if you have the option, do not live with women, except in the case of being married. You may think it's cool and progressive to flout traditional living patterns, but they exist for a reason, and you'll find out the hard way.