I am going to third the vet check. I've worked as a vet tech and have always had an interest in behavior problems and house soiling ones can be frustrating.
Whenever there is a change of behavior like this the animal (dog, cat or bird) should be checked. If it is a bladder infection, it is a quick fix. If it is a bladder infection and it is not diagnosed and treated then trying to fix it by treating it as a behavior issue won't work because the underlying cause is still there. Because she is urinating such a large amount, a bladder infection sounds very possible since usually marking and submission or excitement urination don't involve a bladderful of urine.
Since she is not spayed, when was she last in heat? Some females do get a little wonky when they are starting to come into heat, so that is a possibility, but I still would have her checked.
Here's a good article from a veterinary behaviorist on housesoiling issues-
Canine housesoiling (Proceedings) - Veterinary Healthcare . It goes through several different causes.
Good luck with Ezzie. She sounds like she has a great home.