Work on the person that does the cooking. Don't blame them just try to explain your feelings. Ask for help. If the meal they are serving is not what you eat can you make yourself an omelette?
Record your food in Fitday and analyze your nutrients. It will educate you on what your family is putting in their mouth. Above all don't preach, make little changes for yourself.
My family loves spaghetti, I have the same sauce but use spaghetti squash or whole wheat pasta. They don't think of it as abnormal just something I prefer.
Highest weight October 1st, 2011 247.6
Starting weight January 3rd, 2012 227.8
January pounds lost 7.8 = 220
February pounds lost 4.4 = 215.6
March pounds lost 2.6 = 213 (do better in April)
Goal weight 160.4