Offer to bring a dish to dinner tonight, that way you can be sure that there is something that is "ok" for you to eat and then you can probably have some veggies and other good for ya foods! I used to goto my mom-in-laws and she'd bring a spoon full of something full of sugar and not good for my diet. It is not easy, buy you have to decide that you are important enough to politely say "no", and eat for your health. :) Good luck!!