My mom forces me to keep the dog in my room at night but he has the louudest seizures...?

My family has a dog that's really old and sick, but my moms too cheap to take him to a vet , so she doesn't really do anything . Anyway, our dog hates going downstairs, so at night he always comes in my room to sleep. For the past 2 weeks I've put up with this, and every night I wake up at least twice during the night to hear frightening noises and scratches on my floor ,and then I have a terrible night. I explained it to my mom, and she called me ' a b*tch who promotes animal torture and that I'm selfish". I said that she should keep the dog in her room, to which she replied that I should stop mouthing off. Please help... I want sleep...