Sounds like she came from terrible conditions. I seriously doubt she was inside and using a piddle pad! The woman more than likely lied to you.
It is probably going to take some time for Chloe to come around...just give her time and I think she will be fine.
I would discourage her from eating cat food. She needs to eat dog food for proper nutrition.
The breeder is full of you know what....she is not missing where she was or the company of other dogs. She is sad because she has had nothing good in her life. Hopefully that is now over!
I hope you hang in there with her. Please feel free to PM me any time if you need advice.