i personally have cut booze out completely, and its been 4 weeks now! The reason wasnt just the calories in the alcohol, but the food I would eat when I was hungover the next day. There is just no way I can get through a hangover on shakes and salad. So I have 3 more weeks, then I HAVE to go and have a drink to build up my resistance for my friends hen party the weekend after!!
I think its all about what you can cope with, I know I have a killer headache from just 2 glasses of wine, so it isnt worth the hassle for me. But like the others said, as long as you count the calories and dont go too overboard, it should be fine.