Everyone in the UK is a friendless loser. Not my words, but those (slightly paraphrased) of a recent Snapchat survey that found British people have fewer close mates than other nationalities. With 2.6 “best friends” on average, compared with the frankly excessive 6.6 boasted by participants in Saudi Arabia, and one in seven of us reporting no best friends at all, the results paint a damning portrait of a seemingly lonely populace. A nation of Briton-no-mates.

Mind you, new research by MIT reckons humans can only cope with a maximum of five close friends, so we wouldn’t know what to do with more even if we had them. These findings corroborate 1990s research by the British anthropologist Robin Dunbar, who suggested a correlation between brain size and social relationships. In other words: humans are only capable of having a finite number of people in our social sphere at any given time, because we’re all a bunch of numpties. Now, I’m no scientist, but based on how dramatically my stress levels spike whenever I receive more than one text message before 11am, I’d say that checks out.

Despite being a significant cornerstone of a healthy social life, friends can be strangely transitory. From our first encounters in infant school, when we bond over crayons and crisps, to agonising encounters in our 20s, when we bond over sexual attraction and hating the same people on Twitter, the makeup of our social circles will change in accordance with how we – hopefully – evolve as individuals.

That first core group becomes a rotating cast. Some may remain as key protagonists, others are recurring characters, and there will inevitably be many, many regrettable cameos. But in these fraught, isolationist times, let us take a moment to consider our mates. Who are they and what can they tell us about ourselves?

School friends

Our first comrade of convenience, the School Friend enters our life before we’ve had time to develop a personality. This is especially cruel because these are also our most formative years, so everyone remembers everything. Think of all the names you still know in full, the faces you remember, the houses you can still picture, the girl you were briefly close with in year 5 because you got put in maths together and spent the entire class trying to see how many dicks you could draw on a rubber – and then basically never spoke to again. Mad, really, how GCSE results day isn’t also accompanied by a gracious ceremony in which everyone has their memory erased, Men In Black-style. Seems like an oversight.

Once you do start to find yourself, these early connections go one of three ways: you drift apart in secondary school and never hear about them again until your mum bumps into their mum in Sainsbury’s; you stay friends long enough to have each other on Facebook, where you occasionally like photos of their baby; or you stay friends for ever, know them best of anyone in the world, and are ultimately tasked with delivering a thoughtful but humorous eulogy at their funeral, during which you break the tension by calling them an “old git” for dying first.

Work friends

You see them the most, talk to them the most and have the most in-jokes with them because you spend eight hours a day, five days a week together in the same shipping container office space/on Slack/behind a bar. But, at the same time, they know the least about you. You have a shared language, a veritable buffet of niche references, but they couldn’t tell you how many siblings you have, or how old you are. In fact, if it weren’t for the office email, would they even know your last name?

You will have lunch together twice a week for three years until one of you resigns, and then you will never see them again until you bump into them at Latitude, where you have precisely one beer and realise the only thing you had in common was complaining about the work toilets.

Sesh friends

An extremely shallow, but incredibly pivotal, relationship, the Sesh Friend is the person who, regardless of time or place, can always be relied on to respond to your Bat-Signal text: “’Spoons?”

These are people you don’t know on any real level, but still share a wealth of emotional experiences with, always ending up on the same tired sofa at afterparties, watching old Talking Heads performances on YouTube while they describe a podcast they once listened to about doppelgängers. Never underestimate the bonding agent that is cracking open the last Tyskie to share as the sky turns cold.

Beyond these semi-deep 5am experiences, you have no involvement with them whatsoever. You have never once met for coffee, would never dream of lending each other money, and the only chats you have outside of the sesh are regarding where to meet for the sesh.

Internet friends

The Internet Friend is basically the inverse of Sesh Friend; they know everything about you except what you’re actually like. They’re clued up on the tedious minutiae of your life – what aesthetic you’re feeling at the moment, what mood you were in at 6.19pm last Tuesday, how you couldn’t have a burrito for lunch because the place around the corner from your office was closed for some reason. You exchange playlists, long emails, constant DMs; perhaps you even send each other gifts in the post. But they have no idea about your physical presence, your tics and mannerisms, the geometry of your face cracking into a smile at that gif of a puppy jumping into a bush.

The Internet Friend can be a guiding light. You might call them your closest friend, until you meet them. Never do that

Nevertheless, the Internet Friend holds an enormous amount of weight. The distance means you often tell them things you might find difficult to say IRL, especially if you spend a lot of time online because you’re struggling in your social life. Whether you met them on Tumblr, in a forum for people with a specific medical condition, or through a zealous appreciation of each other’s crap tweets, the Internet Friend can be a guiding light, offering support from the other side of the world. At certain points, you might even call them your closest friend.

Until you meet them, that is. Never do that.

Uni mates

University is a microcycle of your entire life in friendships. You spend the first year talking to everyone, throwing shit at a wall to see what sticks. By the second year, you might have two or three different socials circles that overlap, Venn diagram-like, containing people you like to varying degrees.

By the third year, you can’t be arsed. By now, there are about four people on the entire campus you get on with, and you’re too tired to keep putting in work with the rest. The likelihood of those four people genuinely enjoying each other’s company is even slimmer, so you spend the last 12 months of your degree either enjoying one-on-one hangouts, or going out in massive groups of people whose names you’ll struggle to remember when tagging your graduation photos.

Alternatively, if you’re more socially forgiving, you will end up being added to a 23-strong WhatsApp group called “YOU-NEH [beer emoji]” that pops off a few times a year whenever someone floats the concept of meeting up – which, of course, you never do.

Frenemies

Too many of us feel compelled to stick around people we don’t like simply because they’ve been there for ages, or we did, at one point, consider them a friend – but frankly, life’s too short for that. If you’re fundamentally at odds with someone, stop forcing those awkward monthly catch-ups at Costa, the ones that end with a Kardashian-style barny because you said something uncomplimentary about their new squeeze, and cut them out. Who has the time?

Equally, though – is there any greater driving force for success than hatred? Do the achievements of a frenemy not spur you to greater heights? Do your own achievements not then feel even sweeter? Ultimately, a frenemy’s value is dependent on how you fare on bitterness and competition. If the answer is “I thrive”, then these might be the greatest relationships of your life. Why do you think Fleetwood Mac were so successful?

Background friends

Twitter user @queentrashcan recently defined the background friend in a viral post, which read: “i don’t fit in with any particular group of friends. they all are closer with each other and i sometimes link on but am permanent with no one. i think about all these people constantly but i don’t think i cross their minds often.”

Who has not, in the toilet at a party, worried if you died tomorrow, no one knows your favourite song is Californication

Basically the concept is: a lone wolf who has no established friendship group. This is someone you always say hello to on a night out, ask who they’re with, then realise it’s you. While you have nothing but good things to say about this person, you rarely invite them anywhere because someone else always seems to. Everyone assumes the background friend is better friends with someone else, while the background friend themselves is elusive; familiar to many groups, but a key player in none. Big Donnie Darko energy.

Honestly, though, I’m not convinced this is a real thing. People are emotionally stunted and rarely vocalise what other people mean to them, so I would argue that the background friend is a state of mind more often than it is an identity. Then again, who among us has not had a quiet moment in the toilet at a house party, thousand-yard staring into the cabinet mirror, worrying that, if you died tomorrow, there might be no one who knows your favourite song is Californication.

Playgroup pals

There are some notable downsides to being a new parent: the temporary dip in sexual activity, sleep deprivation, having to raise a healthy, happy baby in the context of humanity’s uncertain future on our rapidly dying planet. But the worst has to be taking your kid to playgroup and having to talk to other parents. And so, for a time, you will spend several hours a week listening to Karen talk about getting reiki for her swollen feet, and you will smile politely, and say, “Oh, that’s interesting” even if it isn’t, because she’s the only adult company you’ve had all week.

These are the ultimate in circumstantial friends – like partners of friends, or the relatives of long-term partners, whom you must accept as your own, despite having nothing in common.

Best friends

Best friends comprise the most fulfilling, longstanding and volatile relationships of your life. These are the legends who will support you unequivocally when you’re going through a rough time, but will also tell you when you’re behaving like an arsehole or have food in your teeth. Of course, the closer you are, the deeper the arguments – but, ultimately, these are the smug bastards who know you better than you know yourself. A best friend will listen to your worst thoughts and not judge. A best friend will rib you when you need humbling, and cook for you when you’re down in the dumps. Most importantly though, a best friend will let you post a photo on Instagram in which you look great but they look truly awful, because they know you’re trying to pull someone. Genuine allyship.

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