That has happened to me a couple of times before, and i must say it is the most awkward feeling to go through. As usual you cannot start blurting out stuff with people you just met for the first time right? You will taste the waters before jumping in. Anyway my most awkward moments have happened when i have heard to sit down with a guy i don't know. Here is a scenario where your friend asks you to accompany her to a date to meet someone new, then he also brings someone along, so you are stuck with this guy who is totally not your type, he doesn't seem to impress you in anyway, and you have to keep him company, what do you do then? you will probably start asking questions, talk about the whether, the food you are eating, the waiters and so on, and when they are all over you have nothing more to say, next there is the stares of the people you accompanied and you realize they are having so much fun in their conversations, now that's an awkward place to be.