We all have a 'friend-in-law'. You just might not know it yet.

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There is a woman I've never made plans with and yet I feel emotionally bound to her in ways I cannot fully explain.

I've never texted her. We're not Facebook friends. I don't even know her birthday.

But I know she had food poisoning on the group trip to Byron last year. I know the name of her ex (the toxic one). I know she has a sister named Liv who got married six months ago, and that she cried about it (but like, in a complicated way). I know she doesn't eat gluten unless she's had a few wines.

Watch: What type of friend are you? Post continues below.

We are not best friends. But we're not strangers.

She is my friend-in-law.

You know the one. She's always around, always in the group photos, always across the table at dinner. You split fries. You swap mascara tips in bar bathrooms. You've cried in each other's presence (multiple times). And yet, there's no direct line. You've never hung out one-on-one. You've never DM'd outside of replying "omg same" to a story about a bad date in the group chat.

She is socially present but emotionally unconfirmed. You are spiritually entangled but logistically irrelevant.

So, what is a friend-in-law?

A friend-in-law is someone you are deeply familiar with through your mutual friends, but who is not technically your friend. She knows things about you, too. She might have borrowed your lip gloss. She once held your bag while you threw up vodka raspberries at a hen's night. But your connection only exists in the context of others.

You will both always be friends with that one friend who introduced you, but that's the only real thing you have in common.

You never message each other directly. You've never hung out just the two of you. And when you bump into her alone — without the buffer of mutual friends — your entire body forgets how to behave.

Do you wave? Do you smile politely? Do you dive into a bush and pretend you didn't see her? This is the curse.

And it is, let's be clear, a uniquely female one.

Because men don't do this.

Men don't emotionally spiral over someone they've met six times at group dinners but never solo. Men don't feel rejected when they're left out of a coffee catch-up between two mutuals.

Listen: Jessie, Em and Holly discuss the friends who don't make your social media grid. Post continues below.

Women, on the other hand? We build entire psychological houses on the foundation of "we laughed at the same thing once."

We remember everything. The vibes. The dynamics. The shared glances at brunch when someone brought up their situationship for the fifth time. We bond through repetition. Proximity. Overheard trauma.

And when that closeness isn't reciprocated or formalised? It feels like being soft-launched into someone's life with no follow-up post.

How to tell you have a friend-in-law

You definitely do. But just to be sure, here's a quick diagnostic:

1. You've never texted each other outside your Whatsapp group chats.

   Unless you count tagging her in a story with "cutie!"

2. You know her ex's name, star sign, and red flags.

   But not her birthday.

3. You've emotionally bonded — in a group setting.

   You once told her your biggest fear in a bathroom stall at a mutual friend's birthday dinner. But you've never had a coffee together.

4. You hear about her exclusively via your mutual friend.

   "She's seeing someone new. He's hot. She's being chill about it." You react like it's your business. It's not.

5. You panic when you see her in the wild.

   Do you say hi? Pretend you didn't see her? Is it deranged to approach her in the Pilates change room? (Yes.)

6. You've been in the same photo multiple times.

   But you'd never post it, because you're not that close.

7. You fully believe you'd be besties — if given the chance.

   But instead of initiating, you just think about it really hard while watching her stories like a platonic secret admirer.

Isn't a friend-in-law just a… potential friend?

Let me be perfectly clear: NO IT IS NOT. 

This is the part people don't get. A friend-in-law isn't "a friend you just haven't gotten to know yet." She's not in your life waiting for you to make a move.

She's someone whose role has already been defined — emotionally close, logistically distant. And it kind of works… until it starts to feel unhinged.

Because here's the thing: you could reach out. You could say, "Let's get a drink sometime!" But something about that feels illegal. Like you'd be breaking an unspoken contract.

The entire relationship exists on the condition that you don't try to escalate it. That you keep orbiting each other like moons tied to someone else's gravitational pull. And honestly? There's comfort in that. You don't have to maintain the friendship. You just have to show up and laugh at her jokes and hope she thinks your outfit is cute.

So no, she's not a potential best friend. She's a social glitch. A passive emotional investment. A woman you will someday cry for at her funeral, despite never having had her number in your phone.

And yes, that's deranged. But it's also kind of beautiful.

Because even if she never becomes your real friend, she will always be your friend-in-law. Your spiritual acquaintance. Your platonic maybe.

And you'll keep liking her posts. And watching her stories. And rooting for her from the sidelines — like the emotionally over-involved, socially confused, deeply female creature that you are.

Feature image: Getty.