You're probably right. But I could also see how it would be hard for her to do that.
Well, it is fundamentally unfair to kill one dog simply because the other one is dying, which is why dad wouldn't let her think of it (till he hurt his back)... but I had the same situation when Logan's back went out and he had to go. Zulu was really worse off than Logan up till that moment. She should have gone first. And I thought of going home to get her. Even in hindsight I think I should have.