I don't know how your resident cats behave during and after a vet visit, but almost every cat I've had hates the vet trip whether fully domesticated or not. the whole ordeal is exhausting for them and it's not uncommon for them to hide 4 several hours or even the entire day afterwards. This is normal. You are worrying way too much, and this may be stressing her out. Stop worrying about whether or not she is happy right now. She is safe and being cared for, and when you move in a few months, you will be able to take her with you. no cat or even person is always happy in life, most of us dislike change. Apple is hanging in there, and you need to hang in there too. Drink a glass of wine tonight and relax