I didn't go to my office Xmas party this year. My excuse was that I'd had a really hard week at work (I had!) and I was just too tired. The actual truth was that I just couldn't face being in a room full of people for that length of time. And, yes, I got a lot of flack about it from my work colleagues the next day.

I have an app on my iphone which slows down my breathing rhythm. I use it all the time to try to calm myself down if I know I'm going into a stressful social situation. Seems to be effective for me...