Because they're territorial, cats tend to not like newcomers to their territories. This is why Hailey got horribly upset whenever she saw Sam or his buddy around our place. Even though she could not go outside, she quickly decided she was queen of everything inside and everything she could see outside. We'd hear growling and spitting from both sides.
First, before we talk about stopping scratching, we must talk about the behavior. Cats scratch naturally. There is absolutely no way for you to stop a cat from scratching. Even if you declaw your cat, your cat will continue to scratch, just without claws.
We hear a lot about bullies at school and work, but do you have a four-legged furry friend who is a bully? If you're tiptoeing so that you don't wake the cat, if your dog is positively terrified of your feline, if you or members of your family sport nasty scratches and bites from what should be friendly interaction with your cat, maybe you have a bully cat.
If you're a cat owner, chances are you have other things on your mind than dental care for your cat. But, your kitty needs her teeth cleaned regularly. Even though it might be a daunting proposition to brush your cat's teeth, it's something that cat owners should do on a regular basis, along with regular checkups at the veterinarian.