Not only can you do this, but you will be super proud of yourself when you do.
Can you make a plan to leave and go somewhere else if it gets to be too much? A movie by yourself, or the library, or the mall, or a walk. At some point someone is likely to comment...are you prepared for the questioning?
We/someone is always here. You can always come here if they start to get to you.
I've done many a family get-together without drinking, while they all drank. You've already proven to yourself you can do it.
I had more problems with just my family's crazy behavior in general. I'm thinking maybe I might have annoyed them a time or two, as well.