I already tried offering her half, then 3/4, of the asking price. No.

I couldn't do that - give her a check and stop payment. I just couldn't. Plus, I think she WOULD have recourse if I did that. Couldn't she just call the sheriff and say, "This lady bought a dog from me, and then stopped payment on the check. So I want to go get the dog back." I think she could. At any rate, that's not exactly legal, is it? Couldn't she take me to court, or turn me over to collections?