I couldn't help but observe some god-awful "party pick-up etiquette." God awful...
So here's what I know...
(1) If... you are standing right next to a girl for more than 5 minutes and she doesn't give you a smile, or a look, let alone a glance in your direction, she is either fully not interested in talking to you or super immature and playing the high school game. (And if you are 40 plus, you should not be interested in playing that high school game back!)
(2)If... you know you are a pretty damn good story teller, and you are telling a pretty damn good story, and the girl you are trying to pick-up is blackberrying the whole time you are speaking, she is either fully not interested or again, super high school immature. And again, you should move on!
(3)If... your only way of getting a girl to stick around to talk to you is by buying her a drink and you know that as soon as that drink comes, she is going to "have to" go to the bathroom, don't waste your money- times are tough these days. And if you do buy the drink anyway and she does walk away immediately, accept that you were a sucker and try not to let it happen again!