How to Deal With 6 Terrible Roommates, According to Science

Roommates can be great -- especially when you get a teammate who helps you pay the bills, an objective confidante when you've had a hellish day at work, and sometimes even, praise be, a friend.

Then there are the roommates that send us running for the hills -- ready to break the lease, give up the deposit, and live in our car if we have to.

No matter how well you screen your roommates ahead of time, at some point you're going to get a lemon. And while you probably could convert your center console into a halfway decent dresser, we have a better solution.

We asked a clinical psychologist for the scoop on how to deal with the most common archetypes of bad roommates. So take heed of these expert-approved tips so you can keep your lease -- and your sanity -- intact. (Thanks, science!)

Oh, and just remember to make sure that the offending roommate isn't you.

The note dropper

Your roommate seems nice enough in person, but then one day you start finding Post-its.

First, it's only one. "Just a friendly reminder! This is my milk!" But before you know it, you can't go anywhere in your apartment without finding a yellow square of judgment.

You probably already figured this out, but a roommate who won't confront you directly is being passive-aggressive. So how do you tackle an issue with someone you can't even pin down for a conversation?

It might be uncomfortable for you (and them) but you should suck it up and be direct, says Ramani Durvasula, a psychologist, professor, and author in Los Angeles. Tell them to ease up on the notes and to talk with you in person if there are issues brewing. And don't back down when they try to shy away from the discussion.

"Passive-aggressive people do their damage by making us feel guilty or frustrated," she says.

And, if logic and reason don't work, Durvasula recommends fighting fire with fire: Try leaving some notes of your own.

Wait, what? Isn't that aggressive passive aggression?

"It is a backhanded kind of communication," she says. "But it may be what works."

The slob

Hey, where's the sofa? Oh, there it is -- hidden under 17 loads of your roommate's laundry.

Sloppy roommates aren't fun, especially when their stuff starts to creep into common areas. And while you may not be able to force teach them how to be tidy, you can fight back.

"Keep your areas clean. They may be inspired -- or at least confused -- by how you keep your space," Durvasula says.

If that fails, move on to Plan B -- for baskets.

"Lots and lots of baskets," Durvasula says. "At least you can toss their junk there."

The neat freak

On the other hand, some roommates are such obsessive cleaners that you're forced to eat over the sink, afraid the crumbs might spill onto the floor and incite a war. No one wants that extreme, either.

"Have your own zones that are untouchable zones," Durvasula says.

Your roommate may be able to relinquish some of the control -- and stifle the related freakouts -- if he knows it isn't his space to worry about.

But that doesn't mean it's time to go hog wild and splatter the walls with Ragu.

Keep your stuff in some level of order, Durvasula says. A neat freak won't ever learn to love your mess.

The borrower

They're constantly borrowing -- or even taking -- your stuff. The laundry detergent is always gone. Your takeout from the night before mysteriously disappears. After a while, you start to think you're the only one who shops in this house -- and you probably are.

Try to fix the problem by being direct: Ask your roommate to chip in more, or at least stop swiping your stuff so often. You want to keep things civil? Say it's a money issue. Your money.

If that doesn't work: "This feels gross, but … you may have to label stuff," Durvasula says.

The flake

You got a roommate to save money, but now you're always having to float their share of something. If you have a roommate who always seems to vanish when a bill is due, you officially have a flake.

"You can go one of two ways," Durvasula says. "One side is to be the parent. Put it all in your name, pay it on time, and give them a bill."

At least then you'll know things are paid on time.

If you'd rather not play mommy to your roomie, "let them put (the bills) in their name and be prepared for the electronic company to turn the lights off -- that'll learn them," Durvasula says.

The jerk

It's a Tuesday night and you have to work in the morning, but your roommate just came strolling in with five friends at 2 a.m. Why does this keep happening?

If your roommate is inconsiderate, there's really only one way to handle it.

"Set ground rules about school or work nights, and set a policy about overnight guests. It feels very dormitory to do so, but sometimes you have to spell things out," Durvasula says.

Finally, don't take it too hard if things don't change. Some personalities are just too stubborn to adjust.

"If after all of this you're still not finding home to be too sweet, it may be time to find a new nest," Durvasula says.