I just read the whole thread and feel so sad for you and the dog. She looks so scared and unhappy - maybe something happened in her life ...
Its a good thing that you donīt want give her to a shelter/rescue because there are so many dogs and with her aggressions it would be difficult to find a new home early. And it would be the 4. place for her, am I right?
Is there a possibility to go with her to a dog school (in germany we call it so) where she can be trained for loosing her aggressions? I think it would be not so expensive than a dog trainer.
I wish I could help her and you.
Please, let us know what will be happen.
I wish you and Emma the best!