She does like walks. Perhaps she can stay.
I'm sorry, but this just sounds really flippant. Like you don't really care one way or the other if Stella stays, you're more worried about her messing up the carpet and lossing your security deposit on the apartment. Maybe I'm reading it wrong, maybe you're just too stressed about other things and your words are coming across not how you intended, if that's the case, I'm glad I'm wrong.
I've lived with four dogs in a single apartment before. It can be done. They were happy, they were well exercised, they didn't trash the place and I even got my security deposit back when I moved. If she's not a destructive dog to begin with, then living in an apartment will not make her destructive.
Plenty of people with Great Danes live in apartments.
She can go with you if you want her too. If you don't....
As far as the situation with Bins goes, I would say you're doing the right thing IF you hadn't said you previously had the money for his surgey and now you don't. Why didn't you have the surgery done when you had the money?
I just don't understand how someone can have the cash to get something so important fixed, and then spend it elsewhere??
How about a loan to pay for the surgery? If you have even half-way decent credit most banks will give you a personal loan.
How about a credit card for Bin? Again, anyone with decent credit can get a CC, get a couple if you have to if the limit won't be as high on newer cards. Several $500 limit cards can cover the costs.
I also believe that many vets have an option called "Care Credit" (or something like that) which is a card just for large vet expenses. I know someone who had a puppy with parvo and she used the Care Credit to pay for the vet fees which were over a thousand dollars.
I have to agree with whoever said, where there's a will there's a way.