Ketamine use on young adult

[Sarahdr]

I don't know where to start. I'm trying to process what's going on with our family.
My daughter is a 21 year old, loving, sensitive and caring girl who's about to graduate. A girl without any issues other than difficulties making friends.
We found out she's using ketamine at home, she brought her new friend (a young boy her age) home and stayed in her room. They had loud music on and when my husband chapped the door repeatedly she didn't answer. We open it and found they both sitting, cathartic, eyes staring nowhere unable to say anything, totally absent.
Took my daughter to the living room and checked her vitals, before phoning 999. She was conscious, slurred speech but responsive, pulse ok, hr a bit high... After threatening her friend with phoning the police he told me they took ketamine... She was slowly coming round. It was the most frightening experience I've ever had!
It's been a week and she agreed to see gp and being referred to community addictions teams. She said to gp she uses 2 a week!
I didn't see this coming. I knew she was hanging out with new friends, that her bestie is a manipulative bitch we've been years trying to keep them apart... She seemed motivated and happy to go abroad to study a masters degree (we thought it would give her the chance to put an end to that toxic friendship) and now she wants to leave home to live with her!!!
I'd like to believe the addiction is not deeply rooted, she's still at her job and working at uni, seems to live a normal life. But she's lost a lot of weight, has mood swings, always seems angry, on the edge, eating very little and she's drop off her gym sessions. I've also noticed a change in her appearance, outfits and disregard for personal hygiene.
I don't know what to do, how can I support her best and take that silly and dangerous idea off her mind. She's too vulnerable just now to take that decision, she needs to get her drug and mental health (anxiety/depression) issues sorted. It seems that every time we asked her any questions or give her any advice the distance between us is further away. Realistically I'm aware she's 21 and there's no way I can mtop her.
Through this post I'm just taking some weight off my chest and hopefully some advice from someone who's been through this.

When did you find out?

Look up how it messes up your bladder. It will make her incontinent. There are loads of pretty young girls telling their stories about this. It might help get through to her. She will care when she end ups wearing nappies.

I don’t really know much about ketamine other than it’s incredibly common among young people these days. It should class as an epidemic, really.

Pull up bladder stories (it’s actually scary tbh), even weed would be a better option if she feels too overwhelmed with life.

Thanks for the replies. We talked about the bladder lifetime problems and how it damages the brain on young people... She's been also experiencing with mdma, mushrooms and dope. I found a notebook detailing her trips on some drugs.
My main concern is how to keep her away from her friends and avoid conflict when we talk.

A week ago, but says she's been doing it for a couple of months.

It's been a week and she agreed to see gp and being referred to community addictions teams. She said to gp she uses 2 a week!

good on her for going and being honest
but…. What plan did the gp suggest?

@Sarahdr it will be near impossible for you to keep her away from that crowd, it needs to be a choice she arrives to on her own.

so much this.