lost,gained...someone help!

Hello
I was married in July and had lost 20 lbs for my wedding. even tho I had about 20 more to loose I felt pretty good on my wedding day. Now, 4 months later, im struggling with the upward climb of those 20 lbs creeping back up. With thanksgiving 2 weeks away im scared that i will be more out of control and the fact that i will be seeing family makes me want to just stay at home and eat! How can I pull it together and keep on track? this is my first time on this type of diet. My friends are doing it and love it! says it's easy.....I need motivation to get going....anyone out there have some words of wisdom for this desperate soul who needs to get a grip? thanks