I want my husband's family to make us a vegetarian or vegan option when we visit them for dinner.
Oh, okay...Why do you want them to make a vegetarian/vegan option for you when you come to dinner?
I don't eat meat and I want to make sure there's something for me to eat.
I'm sure it's difficult to be invited to dinner and make sure your dietary needs are considered. It's acceptable to tell the hosts what your dietary requirements are because it gives them notice before they prepare the meal.
I have to have fresh vegetables and its best if they can use non-dairy cream, olive oil and lemon juice to cook with.
I know that its important to be able to have our dietary needs met, especially if an allergy is involved. However, we should also be good guests when invited to other's homes and not be too demanding with what the meal should be. Most people can understand needing a vegetarian option these days, but try not be too specific in your demands in order to be a better guest.