I think some people may think you are exaggerating about your cat's reactions to being at your mother's house. But I have two cats here that are really my "father's" who react the same way when my father comes over. I use quotes because he abandoned them and is abusive to them when he sees them. Less now, since he is not living with them though. Okay, there is one male tabby and there was two female siamese, the small one always had terrible sores on her when my father was taking care of her. Well, he threw both of the siamese out on the street when he came over and I was sleeping. I never saw the bigger, older one again. But the smaller one came to the door one day after about two-three weeks and I let her back in. She looked like she hadn't eaten at all. Now that she is back, all her sores are healed. But whenever I use the broom for instance, they run away frantically like my father abused them with it routinely while I was on vacation (they never ran like that before I went on vacation). They also run and hide when my father comes in the house. The siamese cat was so sweet and friendly when my father got her, now she is so scared she won't even come close to anyone. Dogs can also get PTSD. My ex-boyfriend's parents used to be foster parents for labs. There was this one that had to take psychiatric medication and was so afraid to go with in at least 15 feet to the street or a car. He would freeze and start trying to walk backward. My ex-boyfriend had to carry him every time we took him for a walk and the dog was so huge too. We also had to take special different routes to walk him. The dog was really sweet though.

Yeah, I don't think you should take your cat back to your mom's house. She doesn't need visitation rights. Cats and dogs can't have therapy like we can, so it's a lot harder to help them deal with their problems. And cats are so much more difficult than dogs. You just have to avoid whatever makes your cat upset.