I’m sorry you are not getting what you wanted. I didn’t think having to room with your sister was so terrible. Some people feel s randomly picked stranger more stressful.
Now it’s not an issue. I figured the chances small you can just order up a two room suite for your kids at most schools.
It’s your parents’ money. They don’t have to give you a dime. Or a place to live or anything. You are 18, you can walk out the door and do it on your own. Anything they offer to you at this point is a gift.