Here is a list of how and how not to act around your ex:
-Play it Cool
No matter how nervous you may get, just play it cool. Easier said than done? Maybe. Composure is key. Having a cool, calm, and collected attitude is the best thing you can do, taking the focus off of any awkwardness.
-Check your feelings at the door
Whatever happened between the two of you during your relationship is now irrelevant. You're broken up. There should be no reason to fight. If you still have feelings for the person, suck it up. It is better if the person believes you do not have feelings for them anymore. Avoid giving them any power at all costs whatsoever. If they know about your residual feelings, it is going to be a very, very long night.
-Stand up straight
Maintain good posture during a conversation. You want to make it seem like you are doing just fine without them, holding your head up high in the process. There is no need to mope around. Exude that confidence. Walk around with some swag. Continue to display any type of independence.
-Plan an escape route
Make sure a friend or whoever you're with at that given time knows the situation you are dealing with. Set up some sort of rescue signal. Clap your hands, cough loudly, or start cawing like a bird -- whatever. Stuck in forced conversation is terrible. Stuck in forced conversation with your ex is even worse. If you're alone and none of your friends are around, make believe your phone rang or your friend texted you saying they need you. Get creative, people.
-Bring up your relationship
Having your ex bring it up is inevitable. If they do bring it up, tell them that you would prefer not to talk about it. What's the point, you know? Unless you're trying to mend the wounds and fix whatever needs to be fixed, it is useless to talk about it. There is no need to rehash bad memories. Bringing it up also lets them know that you still care. Let them miss you. Don't show that you miss them.
-Talk about your current dating activities
Let it be a mystery. Let them wonder what you're doing. Let them think whether or not another guy or girl has your attention. If you're in a committed relationship then I guess you have no choice. If you bring it up, you just sound like you're trying to make them jealous. And if they tell you about their current dating activities or that they have a significant other, act as supportive and happy for them as possible. Grin the fakest grin if you have to. Pat them on the back for all I care. It all stems back to showing them you don't care and that you don't miss them. Keep the ball in your court.
-Get drunk, confess your undying love, and tell them how much you miss them
Yeah -- I think we all know to avoid this one but -- unfortunately -- it still happens. If you feel this way, it should have been brought to their attention in a coherent manner, without a drink in your hand, away from a bar.
-Spend your entire night with them
Look - I understand you might miss them and seeing them brings back all sorts of memories, making it hard to not want to hang out with them. It can be a pleasant surprise running into them. Still, make sure you do not hover over them or suffocate them or follow them -- even if they want you to. I continue to stress the importance of hiding the way you still feel about them. I'm also stressing the importance of presenting your independence.
Act like you don't need them and try your hardest to walk away from them. Every now and then, walk past them, strut your stuff, show them what they're missing, and chat for a bit. That will get them thinking just as much. Make sure you're talking to other people and having fun with your friends. They should not dictate the way your night goes.