It's a slow process, be patient and consistent with her. We adopted Bolt 6 years ago, he's 12 y/o and 3/4 Africain. We don't know his history, but at some point he got into a dog fight. He has the scars to prove it. When we walk, there are certain dogs that will trigger a violent reaction from him. Over the years I've gotten very good at reading other people, and how they walk their dogs, plus reading their dog's body language. A high straight up tail tightly wagging will send him off the rails. I've worked extensively with him to the point that he is manageable when he sees other dogs. I usually make him sit, or give as wide a distance as I can allow. BUT, he is a biter, so I'm extremely cautious when I'm around other people. All bets are off if that other dog is not leashed!! It does get better, and yes you can teach an older dog new behaviors, I certainly did.
