Bit of background here first, I genuinely feel like I have found the one, a year and a half since I first started seeing her I still get butterflies when I see her face, she means the world to me. The only problem has been her drinking, when she gets drunk she is out of control with no sense of safety or what she's doing, and she is quite a naturally flirty person which has caused arguments in the past and eroded away part of my trust, she got accused of cheating on me and I decided to believe her that she didn't, which was hard for me to do and still annoys me to this day with the thought of "maybe she did" although Im 99.9% sure she didn't. Our relationship reached a crossroads about 4 months ago and she promised it would change in terms of her drunken behaviour and I told her about me not being as trusting, both of us have worked hard at our relationship and seems we're looking good.
However she is now wanting to goto magaluf with just her and 3 girls, 2 of which are sluts for 10 days without me. I wanted her to be able to go away and enjoy herself on a girls holiday but going somewhere like magaluf with only the 3 friends (all her other friend want to goto music festivals which aren't really her scene) is a thought that is driving me insane, we've argued about it and she is standing pretty firm that she wants to go there. I thought right I'll just have to get used to the idea but now I'm realising that despite how much I love her I dont think that I can genuinely cope with her going there under the circumstances and I feel strongly that it will be the ruination of a relationship which I want to last, we both love each other but I really don't think I can put up with her going to magaluf and feel like saying it's either me or the holiday, especially after me just regaining my trust for her fully, any advice?