Hi Kellyanne,
Can't you have your CD shake about 1/2 before you go. Bring a couple of bottles of cold fizzy and/or CD flavoured water with you. Also, I went to a party last week and I made up a tray of raw (low GI) veggies and brought that. Then, I walked around with a wine glass of fizzy water and a little plate with the veggies and nibble/drank that. I had a great time.
Also, when other people started (a few always do) getting a bit tipsy and made fools out of themselves, I thought, "That could have easliy been me, because it does not take very much alcohol to affect someone on a VLCD." Then, the next morning I felt good because I made a plan and stuck to it, and I was not hung over! I felt even better when I weighed later that week and showed a loss.
It is hard, but it isn't forever. Every time you go off plan, you delay your arrival at goal. So, you can either take the winding road (a little longer but you'll get there) or just go "as the crow flies". It is all about choice. I am sorry if this sounds preachy, what I am trying to say is we all have our blips, weaknesses, etc., but it is up to us to choose what we want more.
Whatever you chose, do not have any regrets or beat yourself about it (that's pointless) and have a great time. (Be careful re: alcohol and this diet, though.)
MM