Finding an apartment is hard. Finding a roommate with whom you can cohabit peacefully is even harder. One solution to this dilemma is to bunk with someone you've already carefully vetted. A person whose bedtime routine and eating habits you know like the back of your hand, and whose mom you also call "mom" — in short, your best friend.
But, living with the Monica to your Rachel (or the Rory to your Lorelai, or the Marnie to your Hannah) comes with its own set of challenges. It can be difficult to tell your bestie that you need your space — or call her out for pilfering your snacks — without jeopardizing the friendship. So, in honor of National Best Friend Day, we present to you a collection of TV moments that explain how to successfully live with your BFF.