keeping TTC to ourselves -- how to socialize?!

Katie • Momma of one amazing little rainbow girl.
Ok, a bit of backstory here...
DH and are are JUST starting TTC and want to keep tension low by keeping it to ourselves. We aren't party animals, but often have drinks with friends and whatnot. While my friends are never ever pushy for drinking, I have another unique scenario this weekend. I am literally ovulating and need to stay off the sauce. 
I am co-chair of and presenting at a big conference this weekend. As co-chair, I will be mingling with all of our presenters and exhibitors at the social events. Obviously I can stick to Virgin drinks when ordering my own, but people tend to buy others drinks at these events. I don't want to let the cat out of the bag, but don't want to drink
Anyone have any suave tips?