Listen all you can do is try an work with her. Don’t feel like your failing you are doing everything you can. She may just have to have her walker for her life time but that doesn’t mean you give up an try all you know to do. For that vet to give you such a grim outlook for her I think y’all are doing great and she is eating good which to me is a very good sign she isn’t giving up. I know your totally devoted to her and her you but maybe you need to give her some time out too where you know she is safe and you can have some time for you?