I am truly sorry for your loss. It sounds like you were trying to do the right thing. If she had been having regular vet visits and nothing was found then, you wouldn't have any way to know that this was occuring. Quite often bloodwork will not show anything abnormal when some types of cancer are involved. If she didn't give you any indication that something was amiss until you just recently took her in then you would have no way of knowing how ill she was. They often hide their symptoms from us until it is too late. I think what you were doing was the correct thing and that you couldn't have done more unless you knew way in advance what was occuring. You did your best for her and that is what counts. I hope this eases your mind some.
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