Ugh, My Dad Needs To Rethink Things

So my idiotic dad doesn't get why I'd get annoyed when at 7:30 he tells me to get in the car to get soda. I don't mind us having soda around but we just blow so much money on it every week and he gets mad when I try and cut corners. We buy about 10 or 20 cases a week and it disappears in the same week. It just shows the descent into unhealthiness which is starting to become bad. He literally told me I had to get strictly soda, I couldn't get anything like a case of lemonade because he won't drink it. Well he's not going to drink about 1/2 of the cases we buy anyways because my brother drinks a lot of soda and has friends over a lot. I'm trying not to drink as much soda so I buy things that aren't carbonated and he gets mad at me. My house is just drowning in unhealthiness and any attempt I make to change that gets met with my dad making things worse. I try to go to the store with my dad when he goes so I can buy fresher foods so we don't order out or eat frozen food as much. Because I was sick last week I didn't go to the store and was proud of myself with my giant basement freezer having been half empty for a couple of weeks. Right when my dad gets back with my brother they fill up the freezer. The problem with us buying frozen food isn't just because it's processed food that's not healthy but we just leave it sitting there and when my mom or I stick our heads in the freezer we order out because we don't think we have food. Now I know we have food in the freezer but it's all snack food, my dad doesn't buy stuff fit for a meal. He's just spoiled. When he was in the hospital he only drank soda. When they didn't allow him to drink soda he wouldn't drink anything at all, even to take pills. It's just sickening for me to watch my dad destroy his health and inadvertently cause my brother's and mine to deteriorate also. My brother and I are and have always been the healthiest in my family where we'd go years and be fine. Now my brother and I keep getting sick. But it makes it hard for me to manage my weight and properly build muscle with the little amount of healthy food available for me to eat.