Your friend is a sparkling conversationalist who loves philosophical astrophysics and mountain-climbing. Her boyfriend? ... I guess he sort of likes local sports teams and is a self-described foodie for PB&Js. You can't even small-talk about work because he's ... a mortgage proofreader? data entry accountant manager? ... something too boring to remember. Somehow his presence makes your friend a less interesting version of herself.
How it affects you: Desperate for conversation, you'll find yourself asking him "Do you prefer Coke or Pepsi?" Oh god, his boringness has infected you too.
His girlfriend is beautiful, smart, witty, talented ...according to him since you'll never meet her. He swoons over every text she sends, because they are so rare. Meanwhile, she's still liking other dudes' selfies on Instagram and doesn't know how to pronounce his last name.
How it affects you: You'll have to hear him gush over her for months and then pick up the inevitable pieces of the break-up.
His girlfriend is great -- so supportive and caring. She goes to his intramural dodgeball games cheering with handmade signs, and brings sour beer to your party because she remembered your offhand comment that it's your favorite. But he constantly whines about the annoying way she sips coffee too quietly and how good his exes were in bed.
How it affects you: You'll have to avoid her attempts to be friends. Even though she's cool, there's no use in getting attached.
You have no idea what his partner is like since they'll be too busy watching Netflix together, taking couple's cooking classes, and apple picking along the East Coast. When you do manage to talk to your friend, it will be unintelligible -- all his conversations will involve inside jokes and shared experiences you're not a part of.
How it affects you: You won't see your friend until the break-up, when he'll emerge a single butterfly ready to party from his months trapped in a couple's cocoon.
You thought you could find good in any human, but your friend's boyfriend provides a challenge. He's the opposite of everything your friend values. This relationship was doomed from the start, but she couldn't resist the antithesis of her.
How it affects you: You'll have to grit your teeth and silently watch your friend make terrible mistake. Whenever she says anything slightly negative about her partner, you'll try to encourage it without going too far. When it's all over, you'll spend hours searching the internet for a good therapist that accepts her insurance.
You'll meet his new girlfriend when she busts through the door of your party demanding to speak to your friend. Ten minutes later, they're getting handsy on your couch. It's something straight out of a romance movie, but the real-life version is just exhausting to watch.
How it affects you: In an effort to comfort him when they break-up, you'll tell him how annoying she was. Each time they get back together (and oh, they'll be on-and-off for years), you'll have to dodge her dagger gazes.
This will be an unremarkable, short-lived relationship from a trip abroad, rekindled by one visit then never again. However, your friend will spin the brief memory into The Notebook meets Princess Bride meets the entire Before Sunrise series.
How it affects you: You'll hear the same romanticized sob story over and over and over and over until your friend finally meets ...
Great, she finally found someone worthy of her. They are both perfect for each other and set relationship goals for your shitty love life. They're moving in together, so I guess your best friend commune plan is over.
How it affects you: Your friend's happiness has sentenced you to a life of third-wheeling. ... Do you still have Asshat's number? He wasn't really THAT bad, right?