Hello Gill my name is ***** ***** I will help you.
What is it you want to achieve please?
Do you have a number we can chat on?
In summary she has very little rights. She can only 'occasionally' and this can be with you present, unless it was agreed otherwise.
Just because no money changed hands does not mean there is not a valid contract - there is,
You have paid for vets bills etc and had to deal with an aggressive dog.
I hope this helps.