My Pre-Op is 5 shakes a day, the first few days were hard but after that I was OK, even went to a friends House Warming party yesterday there was a big crowd there and they made some great looking BBQ food, but I was not tempted to indulge, they also had a lot of booze on the go and me Originally being from Scotland (we like our beer)never even touched a drop.
Stick with it it gets easier and it will be worth it in the long run!!