To be quite honest... its your dang birthday, go nuts! i.e. Enjoy yourself
I've lost 85lbs having an off day of whatever I want, including drinks, at least once or twice a month.
I've come to realize that skinny girls have off days here and there and enjoy themselves... the difference between us and them is that we go overboard at every meal, or every day... whereas they have their fun when its time to have fun and then go back to NORMAL, sensible eating without batting an eye.
This approach has definitely worked for me.
Word of Warning though.... once you go "overboard", it's somewhat hard to go back to eating right. Your body gets all those crazy carbs and fats and sodium it was addicted to before, so you get the urge to keep going that way. DO NOT LISTEN. Go right back and get on that wagon. Soon enough, you'll find it normal to have a fun girls night out here or there and enjoy yourself without binging for a week afterwards.
Happy birthday by the way