1. You’ve survived the awkward teen years together.
Nothing can glue two people better than trudging through the horrors of middle school. All that math, and all those raging hormones. It’s like a modern version of a blood pact.
2. You know each other’s crushes and exes. All of them.
You don’t ever make her forget her romantic fling with Onion Breath Guy, because she always reminds you that all your notebooks in 12th grade were scribbled with “I <3 Mr. Belcher.”
3. You also know all their secrets.
Like the time they played hooky for a day when Weezer came to town. But you’ll never tell anyone, ‘coz you played hooky right with her.
4. Embarrassing stories? You have an entire archive of them.
And you’re ready to pull them out at any given moment. Blackmailing is easy when you know that she used to be called Chewbacca in high school because, well, swimming attire and really hairy arms apparently are a mismatch.
5. Their parents treat you like family.
You love coming over to their house because your best friend’s mom always has something baking in the oven, and you enjoy playing pool with her dad. They’re like your own parents, except cooler.
6. You love reminiscing about your childhood.
Naturally, you can talk nonstop about anything under the sun, but your favorite sentences start with, “Remember that time when..” Once someone starts, it’s an endless — but fun — rabbit hole that takes hours to climb out of.
7. Another topic you love talking about? Other people from high school.
There is nothing in this world that is more fun than gossiping about the people you went to school with. Whatever happened to that momma’s boy who always threw tantrums in class? Or the girl who never wore deodorant but got knocked up before graduation? And how about the kooky nerd who not only built his own company, but also has Ryan Gosling abs?
8. You both know that you can be your wacky, real selves with each other.
Your friendship is kind of like taking off your bra at the end of a long day: you can just be sad and saggy but that freedom is the best feeling in the world.
9. They’ve seen you ugly-cry.
And heard you snore in your sleep. And watched your face grow puffy from a severe allergic reaction. There’s nothing they haven’t seen, and they continue to love you despite knowing how ridiculous you look in the morning.
10. If they call you in the middle of the night asking for help to dump a body, you’ll go in a heartbeat.
No questions asked. Because you know they’ll do the same thing for you.
11. You literally have each other’s clothes from 10 years ago.
Crop tops and high-waist jeans have recently become stylish again. So you’re only mildly surprised that your best friend posted an Instagram of her wearing your Mickey Mouse tee shirt from when you were 12.
12. You stayed in touch throughout college, despite being miles apart.
Even though studying at different unis separated you physically, nightly chats about boys and mandatory Skype calls for fashion emergencies made you feel like they weren’t far away.
13. They play therapist to your mood swings.
No one else can mellow you out when you have an “episode”. They’ve already memorized that you crave Big Mac when you’re on your period, eat exactly half a tub of chocolate chip ice cream when you’re depressed, and accept the fact that you just really need to break stuff when you’re angry (RIP her Starbucks Hong Kong mug).
14. You’ve probably touched her boobs.
It’s no longer even awkward. Seriously, you’ve changed in front of each other for more than five years of PE classes, who even cares at this point?
15. Yes, you’ve had your fair share of fights and drama.
You’ve gone from three hours to three months not talking to each other because of something silly. But no matter how many times you argue, you both manage to patch things up and make your relationship stronger than before.
16. Talking to them gives you a nostalgic feeling.
Your twenties have been busy years for both of you, with work and boyfriends taking most of your time. But whenever you do get to talk to each other, the feeling is like nothing else: a warm blanket, or a hug, or finally coming home.
17. You promised to be at each other’s weddings and baby showers.
They were right there holding your hand during some of the hardest days of your life. And sure enough, they will be right by your side for all the other 60,000 memorable events in your future, no matter how good or bad. You can’t even imagine where you would be without your silly, brilliant, sometimes-crazy, always-amazeballs partners-for-life.