I am not in your position and never have been, but if you can't stand to hear them talk about whatever isn't lady-like behavior...be it drinking, sex, or whatever...just simply walk away. If it really starts to bother you to the point where you feel it's getting out of hand, bring it to other people's attention.
In my chapter we call ourselves classy and we do not go around rehashing our nights out...even if they are PG rated.
If you feel a certain way then I'm sure there is someone else in the sorority that feels the same way too.
Good Luck.
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What do you get when you cross an Alpha Omicron Pi and a Sigma Phi Epsilon? A beautiful Chi Omega!!!
Zeta Delta Chapter of Chi Omega
http://www.unomaha.edu/~comega