There are always some concerns when a topic like this comes up. Your initial reaction was actually solid, but what you need to do is be completely honest about your reasoning for disliking the idea of your girlfriend going on a girls’ trip. Sure, that’s a bad friend, but your primary concern is that she’s going out to party and potentially putting herself in situations where her fidelity could be compromised.

Generally speaking, a subtle comment right after telling her she should go and have fun would have been enough. She needs to know that you’re not completely indifferent to it, and that you do recognize the implications of her going out partying, implications that could compromise your relationship. That comment could be something along the lines of, “Yeah, those places can get wild.”

Rollo Tomassi speaks clearly about this and how you should respond. Other senior contributors have also pointed out the red flags in a situation like this. Still, you're your own man. You've been together for eight years, do you really want to throw that away by blindly following advice without adding your own nuance to the situation?

Read more about the concept of the mental point of origin and try to apply it across your life, not just in this one scenario: https://therationalmale.com/2014/11/14/mental-point-of-origin/

Many people here forget that the reason we’re in this space is because we’re pushing back against the programming we’ve received since childhood, only to end up following a different kind of programming to the extreme, without injecting our own thought and nuance into it.

Your GF, regardless of the ephemeral words that come out of her mouth, wants to go on an EXTENDED Girls Night Out™️.

With a girl that not only abandoned her (so much for “girl code”), but is also confirmed promiscuous, and impulsive. AND she’s about to break up with her boyfriend? Damn mate. Nothing is guaranteed, but you do realize this is a perfect storm for a cheating scenario. Was a bouncer for 5+ years, and girls always go looking for trouble in twos. Only have to rationalize bad behavior to one other person that way.

If she sees her friend behave badly with zero consequences, she may partake as well.

If you haven’t already, I’ve had good results laying it out in a 3rd person scenario with a statement of fact.

“Do what you want, but I couldn’t take a girl that goes on holiday with someone like that seriously”

Or even better: “You’re supposed to be my girlfriend right. What does that mean to you?” And just let it hang there.

If she gets the picture, she will protect her relationship and not go.

Its been 8 years,that is a long time. I think you should be worried about the quality of people she is surrounding herself with, and the way they treat her.

Really dude, they left her in the city at 1am,not giving her a ride means they think she is some kind of door mat.The apology is just an excuse to do it again,these things will keep happening if the cycle is not broken. Some people are like that, they love to keep people close they can walk over and stomp, break the cycle and the interest is lost.

This is,and in my opinion should be treated as you caring for her well being and social circles, maybe it is time to let that bitch go and get a new friend.

First off, this sounds like a shit friend and I'm surprised she'd want to go on holiday after this.

Second, I'm reminded of an old Eddie Murphy routine about a woman going on Vacation to Jamaica without her boyfriend. She winds up on the beach by herself and feeling lonely and gets approached by a local who starts putting on the moves. "And then, the next thing you know, some dude named Dexter St. Stud IS FUCKING YOUR WOMAN!!!

This honestly sounds like a disaster. I would give her final say, but be very firm about how her friend hasn't show you that she can treat your girl right.

You could always plan a getaway with her later if she doesn't go with the friend. Sometimes a day trip or desecrating a cheap hotel room is a welcome break.

Ultimately is your job to let her know you think the friend has been shitty to her.

It's hard to say how much to worry. Some girls I used to date, I would trust to go, others, fuuuuucckkk no! There's no reason to make yourself crazy over this and also you shouldn't make it your problem. Say your peace, show loving concern and let her police or behave herself.

You are worrying about your girlfriends friend, which is nothing to do with you.

You should be more worried about your gf.

the very fact that she wants to go on a holiday wihthout you is a gigantic red flag. I am surprised that you cannot see it.

For her to even suggest this means that she has zero dread - she is not afraid of losing you. Therefore, she does not value you or respect you.

I would agree with @Lone_Ranger take - the fact she is willing to go on holiday without you is a red flag. Why not a double-date style holiday? It seems a bit suspicious.

Even more suspicious if they're going to a party destination, where the only reason for going is getting wasted and getting railed.

Rollo has an article about this. The problem is that your girlfriend wants to go without you. When trips come about this way, the woman is going to hook up with someone. Once they get to the destination, they'll go to places to be approached by men. No point in discussing boundaries or any such nonsense-she wants to go, which means she wants hook up options that you won't find out about. That is not the behavior of an exclusive girlfriend.

Don't say anything further about it. Consider the exclusive nature of the relationship to be over and start talking to other girls. If she lives with you, take her stuff to her mom's when she is on the trip. If not, don't be available when she gets back. Just go no contact for a while. Chances are you'll meet someone more suitable and not have any interest in seeing this girl again. Just keep your cool between now and the trip and change the subject if she brings it up, and start talking to other girls now.

Also, stop trying to rationalize your girlfriend wanting to go by thinking the problem is her friend. No, the problem is your girlfriend wants to put herself in a situation where she can hook up with guys and you not know about it. The birds of a feather saying didn't come out of nowhere. Your girlfriend is the issue, not her friend.