Aww so sad. You did a wonderful thing! My collie/shepherd mix that passed away in August showed up in similar health and fear 10 years ago. It took about a year for her to trust and about 3 years to completely settle in. It was worth it all though, every day she would just look at me with the most peaceful eyes and relaxed ears and say "thank you" in her own way. I'm sure it's tough for now but I promise, it will all be worth it!