Story: Well I have been talking to this girl, went on a few dates and she is always saying that she wants to do something again with me, last date went to redskins game (BTW shittiest team ever) and there was alot of mutual kino and kissing.

But this weekend we agreed that we would meet at a mutual friends house for a party, and she brings another guy with. WTF. As soon as she arrived with him she came up to me and hugged me like nothing was happening. Her best friend looked at me like "I have no clue what is going on" and even said to her "WTF are you doing?" in front of everyone.

Well night was actually going good for me with her better then it was with him. Me and her even agreed that we would do something later this week. I left to take my drunk friend home. I come to find out that he tried kissing her and I guess she did kiss him. "Whatever they were both drunk" I thought to myself. Then today I get a text from her saying that we cant do something this week cause she will be up at Atlantic City, and would not say why she was up there.

Well at the party I was using simple Social Engineering and already had figured out that he happens to live in AC of all places plus a lot of information that could get him fired from his job as cop oh yeah and photos but it is not his fault so his career is safe plus I am a strong believer that they should legalize pot even though I have never smoked.

So now I know that she is up there with him. My question to you is what should I do in this situation?

Should I freeze her out?
How should I freeze her out?

I would totally freeze her out. Bringing an other guy? That's almost disrespectful.

I would cut all contact with her. Now there are two options:
(a) In some time she will feel the lack of you and try to reach you. If this happens, then act completely normal as if nothing had happened and keep gaming her.
(b) She will never call. This will only happen if you didn't leave a strong impression before. In this case, why waste your time anyway? Move on to he next girl.

I think probably the girl wanted to try to make you jealous. If you freeze her out, she'll probably feel like she fucked it up and (hopefully) will chase you to try to fix it.

Some girls will never call even though they really want to talk with you. Do you think she might have that kind of personality? In that case, you might try texting here in a week or two with something along:

"I don't remember, are we fighting? And more importantly, am I winning?"
or the awesome zoo text:
"I really miss you and want to see you, but this stupid security guard won't let me in to the zoo. Do you think you can escape?"