I would ask for the dressing on the side and ask them to bring only one bread stick per person. Choose a Marinara sauce over cream sauces if you are ordering pasta. As DRAGONCHILD suggested--have them bring you the take home box at the beginning of the meal! Look at this way---taking half home just means you can spread the celebration out longer! If there are others living in the household mark your name on the box and tell them to back away! It's yours! LOL!
OH--and look up the nutritional info before going and decide ahead of time what you will eat and then stick to that choice! And order first---that way you may not be as tempted to get what someone else is having!
Have a Happy Birthday!