I wonder if Rolo snuck past you with the issues she has been having.
I had been thinking about her, I did ferret rescue for a long time and ferrets can be effected by adrenal disease, which can mimic a lot of sexual behavior in altered animals.
So I started looking up adrenals in rabbits. I found this article. http://www.rabbit.org/journal/4-10/sexhormones.html
It would be interesting if they find they can use Lupron on rabbits. We were able to get Lurpon depot for ferrets and it was wonderful for the ones who were not surgical candidates. With rabbits, it’s not the same issue and surgery would not do anything from what I’m understanding, since it’s their body just using it’s pancreas to continue producing hormones as if they were not spayed. I also had some good luck with melatonin on some of the ferrets. I had a ferret who had been bald for years, due to adrenal disease and on melatonin grew all his hair back and got back his energy and strength and was able to have surgery. I don’t know if melatonin is safe with rabbits or if it would have the desired effect.
I know that was rather long winded, I was letting my hands wander a bit with my mind there.
Anyways, I’m thinking anything small enough to hide in your house would probably have a very small pee puddle, like a mouse or a rat. However, because your girl has been acting differently as of late it just seems likely she said to heck with your roommate.