It's inevitable that you will end up running into someone you've dated or hooked up with. In college, this was every time you went to AEPi or when you decided that you wanted an entire buffalo chicken pizza for yourself. You should have ordered delivery.
Now it's probably at that young Professional People Who Wear Ties and Pretend to Do Work while GChatting Happy Hour. Sometimes you can employ the stop drop and roll technique, or just run away. But sometimes you just have to suck it up, remember that you look hotter than he does, and say hello. It can go one of many ways.
1. Awkward half-smile and wave.
This one is for all of you very non-confrontational people, a half smile and wave that says oh heyyyyyyy yes I remember that thing that happened when you tried to remove my bra but I'm just going to go order another vodka soda with my friends and basically pretend that I didn't see you. I am going to acknowledge your presence, but then forget it and try to make it as un-obvious as possible that I am going to go ask my friends how I look, if I handled this correctly, and to tell me that its such a good thing we ended things at that mixer where I dumped jungle juice on your head/made that big scene in front of the beer pong table. I'm so much better off.
2. The overly friendly.
This happens to those of us blessed with a disease called diarrhea of the mouth. I have a big case of it. And there is no cure. How are you Jon? How are things? How are your parents? Whatever happened with that company you wanted to start? Can I ask you some more questions in a way to mask my insecurities and pretend like everything is fine? Oh I'm great, I know you didn't ask. But it turns out that my project went really well thank you and unfortunately Bernie (my fish) passed away. It was sad, yes. You're going back to your friends now? Okay.
3. Ignoring him entirely.
This could be a dick move, but it's also very difficult to make small-talk with someone who may or may not have undressed you. It's like his eyes are searing through the back of your Japanese-straightened skull, rendering the party, happy hour, or hot-tub social pointless. You kick back several belly laughs that scream I am the life of the party, who are you? but you're not sure how much you mean it.
4. Lying about your new boyfriend.
I've done this before. It just sort of comes out like word vomit. I know, right? Nobody told you I had a new boyfriend but he's great. He's pretty famous actually. Well, he only does indies, you know, to preserve his art. He's writing a screenplay now. In my head.
Why did I just lie? Did I do this in an effort to make myself feel better? What am I going to do when I bring my Sundance award-winning boyfriend to formal? "Josh isn't here actually, he has a huge press junkit in Juneau. With James Franco." I was supposed to go to support him but, you know, I thought it'd be nice to give him some space.
But srsly, what are you supposed to do when you see someone involuntarily who knows about that one time to tried to vagazzle?