So, girl I'm friends with is getting close to one of my guy friends. I had feelings for her, but never acted on it because I didn't like who she was as a person.

Then come this weekend, she starts spending time with a guy friend of mine. They end up sleeping together, which I'm fine with. He talked to me about it before hand and asked if it was okay. I was fine with it.

But tonight, she invited me to go to a highlighter party after her barn dance. They met up, and text me that I should go to the party with them. I leave the apartment party I was at to hang with them, because you know, they're supposed to be my friends. And then bam. No contact. The last text is her saying she was helping her friend throw up. Call the dude. No answer.

Now, I was alright with all this. I'm pursuing other girls, and so I'm not too worried about her. I'm starting to get pissed off though, because my friend, a dude, is being a shitty friend in order to be with this girl.

EDIT:
Just found out from one of the people with them that nothing happened, and they're lying about it. She's fucking taking a good friend from me, and taking advantage of the fact that his recent girl didn't work out. I need to shut her down immediately. What can I do, and or should I just bail on them both?

She was lying about helping her friend throw up? Why did they invite you out just to dog you?

I'd imagine it was mostly the guys fault. She is content with being friends with me as I am, and she knows I'm going after other girls right now. He was being more secretive. She was honestly to drunk. I went out anyways to a frat party, and she told me to come. But i decided to let the situation work itself out. So we'll see where this goes, I just wish there were ways for me to manipulate the situation, or just bail for my own sake.

Another thing I think was the fact that they just wanted to be nice, which is another possibility. He has a history of doing that to people when I hung out with him, of inviting him and just being like, "I don't want to see them." I just thought dudes were out of the question in situaitons like this, especially someone I've known for awhile.