Family won't eat healthy

I've been trying to get my family to eat healthy for almost two years now, but they just won't. Mom has type 1 diabetes, sister #1 is allergic to gluten, and sister #2 only hears me call her fat, even though that's not what I'm doing at all. Sister 1 has never eaten vegetables or fruit in her life, and has resorted to just bacon and eggs, nachos from a fast food place (which everyone says is "healthy" totally not.) ice cream, and processed meats. Mom had to watch carbs, and says eating vegetables and something else (mashed potatoes) is too much starch and carbs. But instead of getting vegetables, she's eats the unhealthy carbs, way too much processed meat and red meat, (hot dogs, cheeseburgers, which she says has vegetables, but I've only seen her put bacon on it,) and no fruit. They both call lettuce, bacon, croutons, and dressing a salad. No vegetables. Sister 2 wants to lose weight, but won't listen to me when I tell her she needs to cut her white carbs (cereal, giant meals she eats from her work that have no nutritional value) she eats more vegetables and fruit than sister 1 and mom, but not that much. Her meals are too sugary, and she refuses to see that. She also refuses to do cardio. Both sisters tell me the advice I'm giving them is wrong, and that I should just shut up, because they both think I have an eating disorder, (I don't, I'm just thin and I like to exercise.) I don't know what to do. But I don't want to sit back and watch them kill themselves, and I'm