I have a friend that's like this too, I think he does it because he wants people to accept him as cool, and unique, which is wrong.
It's good that you're at least trying to tell her to stay away from the party setting, because you really never know what's going to happen!
I'm guilty of breaking this rule too, actually I broke it last weekend.
I was at a house party with half friends, and half people I didn't know in a house we rented with rooms for everyone.
I do a 5 gram tea, and when I feel it starting to hit, I excuse myself from the party.
I start tripping, and low and behold about 40 mins into my trip, a girl from the party shows up.
I don't know if she was drunk, sober, or on something else.
She wanted to have sex, very clearly.
I kept telling her that I wanted to be left alone, and she wouldn't oblige me.
I continuously asked her what the meaning of peace was, and tried my best to get her to leave nicely, she knew she was invading my peace and space and gave 0 fucks.
Then she says "I'm getting naked." and I say "What the hell are you doing?" and then i get up from the bed, and sit in the corner.
Then this girl calls her boyfriend while I am tripping absolute balls, and starts fighting with them, and that sent me on a whole different trip on it's own.
She hangs up the phone, and tries one last time to call me to the bed, and I politely decline and try to enjoy my time as best I could.
I couldn't leave the room because there was a loud party going on outside, and I wasn't in my normal city and it was like... -15 out there, not much option for escape when you're that high.
TL;DR Girl invaded my trip hard, and almost ruined it, always make sure you have full control of a setting, or are willing to give up full control to someone you trust.
And if you trip in a party setting like I did, the blame rests 100% on you, not the people you tripped around, that's the choice, and gamble you took, sometimes it works amazingly, other times not so much.
Don't mix tripping with people that drink, you're likely to be misunderstood, judged, mocked, or worse.