I am so sorry to read this and you certainly tried your very best to help your little dog.
You just probably ever know for sure what was going on unless the Vet dud a necropsy and, sometimes, that isn't even conclusive. It does sound like there was some major issues going on that another Vet may have been able to diagnose but maybe not, and probably would have involved even more testing and surgeries. I doubt you would have wanted your little one to be in that much discomfort any longer.
I had a somewhat similar situation years ago with one of my Shelties who actually had MD. He suffered an esophageal burn as a puppy but he did pull through. I had to keep him on a soft diet from then on. One day, I noticed some bleeding from his nose and mouth and rushed him to the Vet that could do an endoscopy. He had a bad ulceration that would have been hard to manage, if at all. I made the decision to let him go. Sometimes, it has to come down to a quality of life issue, at least for me. I know he would have been miserable and none of us want to see our dogs in pain or miserable every day.
With the information you had from 2 Vets and your dog's symptoms, perhaps this was for the best. Awful when you don't have definitive answers, I know.
She was very lucky to have you!!
Hugs,
Dear Jerry, thanks for your coments!!! and I wish you a great New Year too. I live in an appartment and I checked around but there is nothing dangerous for dogs and my beautiful doggie was well trained and wouldn´t eat anything that was not hers. I do want another dog and it is a good idea to help a rescue dog (I love all dogs and really connect with them)...yet right now I feel so sad about what happened. I want to understand what happened to her, if she wasn´t well diagnosed...¿what illness did she have? Since the start of all this she would throw up undigested food, which I thought was strange...I thought that these vet were good, but now I feel bad to have taken her to them. I think that they should have done some blood work since the begining and the first one didn´t until much later...it kills me to think that this could have been prevented and yet there is nothing that I can do...I feel angry and guilty and so sad...
You didn't do anything wrong... you went the extra miles to help/cure and it didn't work.
You even tried two vets, still I wonder about the quality of the vets, way more than any doubts about your efforts and commitment.
If looking for answers, I doubt you'll find any here but I suggest you look carefully for any hazardous material in your home and areas the dog used to see if the dog cold have ingested something terrible. This is especially important when you get another dog... I think you should and ask you consider adopting a rescue, perhaps an adult that has been house trained and may have trouble finding a home as most are looking for puppies.
You did the best, more than expected, you could. I hope you have a good new year, and had and otherwise Merry Christmas just past.