@Joe08, Let's get a couple of things out of the way:
Your girlfriend is lying to you. She wants you to believe she forgot 2 versions of her inappropriate behavior - first she forgot that she danced with him, then she forgot that she went all "dirty dancing" with him.
But while forgetting all that, she remembered to tell you he approached her, but she sent him packing like she shoulda, but now that you jogged her memory, the only reason she dirty danced with him was because she was pissed at you!
Huh? She danced in a sexual manner with some kid because she was pissed at you?
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Here is the deal. She did what she did at the club because she wanted to. She got liquored up and did what felt good to her in the moment.
Then she started lying to you before you even knew anything probably because she was trying to do damage control and throw you off the scent because she made an ass of herself publicly in front of people who might blow her up later in front of you!
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Take no offense here, but she apparently has the mentality of a 20-year old.
Having said that, I think if this was a one-off, it can probably fall into the "mistake" category.
She went out, got drunk and got stupid. The question is, how far did it go?
And here is the rub: you need to get the truth out of her so you can decide if you want to invest any more of your precious time in a single mom who evidently doesn't know how to comport herself when her boyfriend is not around.
Did it go farther? Are there any other incidents?
IF YOU WANT TO STAY WITH A RISKY PARTNER SUCH AS HER, With the knowledge and point of views shared with you now, you can confront her and cut through the bullshit.
When you confront, you have to "put the screws to her". Do not accept any bullshit!!
And if you really really really want to know what she has been up to, I would do some investigating prior to confrontation, and set up a "surveillance net" for after your confrontation which will catch her reactions afterwards when she is out of your sight, because that's when shit gets real.
But only do that if you still want to stay with her, and that to me is 50/50 at best right now.
If you want to go the investigation and surveillance route, come back and I/we can help you out.
[This message edited by faithfulman at 4:31 PM, December 29th (Sunday)]