1. They don’t judge you.
There are certain life choices we all make which, outside of our own perception, must seem fucking insane. We go out on a whim and get a tattoo of Sonic The Hedgehog across the better part of our chest along with a smattering of genital piercings. Some people would judge that shit, and swiftly. But not your good best friend. This is the person who literally sees whatever you’re doing and thinks, “Is this hurting them or someone else in any way?” When the answer clearly presents itself as “No,” they don’t care. They just don’t. And as obvious a response as this should be to the benign life choices of others, it’s surprisingly hard to execute in practice. If you can find someone who genuinely does not judge you for things you choose to do in life, you hold onto that person with a death grip.
2. They motivate you to be better.
While judging indiscriminately is never a positive, there are certain things that must be judged in order to keep us all in check. If your best friend sees that you are not doing well, not doing healthy things, or not trying as hard as you could — it is up to them to be the mirror that you’re more than afraid to look into. There will always come times when there are hard truths to be spoken, and we rarely have people in life on whom we can depend for some #RealTalk. If you and your BFF are both constantly doing your best and making healthy choices (and encouraging each other to do the same), there is little more to ask for.
3. They keep your secrets.
You think that everyone is keeping your secrets, until you find out that they aren’t. And then it’s just a domino effect of “How Many People Know About That Time I Killed A Pedestrian In My Jeep” until you have a complete mental breakdown. Real friends keep secrets, and it is only a matter of time before you discover that none of us have a lot of “real friends.”
4. You can tell them anything without them treating you differently.
The difference between judging someone and not treating them differently no matter what is simple, and it has to do with what is within and outside of your control. A best friend shouldn’t judge you for life choices that don’t hurt anyone, but they should also not treat you differently if you come on some hard times out of your control. If you’re not making a lot of money, if you have a terrible breakup, if you get kicked out of your apartment for unforeseen circumstances — they still treat you like a good person, deserving of respect. They don’t operate on the “you have to prove that you are a human being we should treat well” rubric that much of society seems so enamored with. They love you no matter what, and aren’t going to suddenly become assholes because you can no longer afford weekly brunches.
5. You don’t have to work for their affection.
There are few worse feelings than being around someone who is clearly less into you than you are them, someone with whom every act of affection is a distinctly uphill battle. And we spend our whole lives working for a little bit of love from the people we’re chasing after. There should be at least one person in life who is an oasis from the “will-they-or-won’t-they-call-me-back” hooplah that is modern dating. With your best friend, things should just feel cool. Sure, you’re going to fight. Yes, you’re going to get angry with them. But there will always be a baseline of appreciation and love that underscores your interactions, one that reassures you that you have nothing to prove as a person.
6. You can be completely ridiculous around them.
Sometimes you just need to re-enact the scene in Spongebob where he dries out completely and stares down a glass of water while repeating “I don’t need it.” Sometimes you need to do it in your underwear, with an audience. You don’t know why, you just do. And that’s when you need a good best friend.
7. Many of your conversations consist entirely of inside jokes.
The thing about best friends is that they will often develop a kind of language between one another, one that becomes so intricate it can often bring them to laughing tears with just a few stolen glances. You understand what the other one means, you know what they’re thinking, and you know how they’re going to respond to a multitude of situations. You become fluent in this language which only the two of you speak, and are able to create a kind of cultural shorthand for the various events and people you will encounter together. For the two of you, it is easier to communicate in this incomprehensible code than to actually sit there and spell out what happened on your last date. Also, it’s very convenient when you’re out with a bunch of randos and want to shit-talk someone without getting caught.
8. You have the same sense of humor.
When you are laughing to the point that you are pretty much positive you’re going to pee your pants, and are doing it on a consistent basis, and over things that almost no one else would ever understand — you know you are with a good best friend. 
