All of the above.
I think that is one of the 'shifts' we have to make in our thinking. Social functions / gatherings, weather they're for Xmas or not, aren't about food - believe it or not (I know, I was shocked too )
They're about catching up and spending time with people. Focus more on the social part of the get together, not the consuming part.
You will find it liberating to go to an event and being able to focus on catching up with people. I know for me, previously at events like this I was constantly pre occupied with what I could eat. I didn't even realise how pre occupied I was with food until post sleeve.
Go with what AussieLady said. Enjoy family and friends this Xmas.
Good luck,
Deano