I have a slightly different take. The homeless need their dogs, and these dogs need people, because numerically speaking, they would probably end up dying in a shelter otherwise. However, we need to accept that, just as the homeless are living substandard lives with little care, their dogs are living substandard lives with little care, and so will die earlier and possibly in more tragic ways. This is an example of that. The woman was unable to take adequate care of the dog, couldn't stay out of jail, couldn't articulate a plan to save the dog. Hence, the dog suffers.