Amanda gave you awesome guidance, Johnna! When working with MP's reactivity, one of the hardest things to remember/stick to/accept (?) was that she can't learn anything above threshold—once she's amped up/freaked out/whatever, brain is shut down, and it's all just stress and instinct. Sometimes it feels like you're not doing anything because the stressor is barely visible/audible, but if that's the distance and space the dog needs, then that's where you start.
Otherwise, you're just making it worse and ruining your relationship. Also remember that stress is cumulative, and some dogs take a long time to recoup after each "thing" that caused stress. You add a little bit along the day, and you end up with a straw-camel-back situation. Like Amanda said, I think building trust and a relationship with her should come first, and you might have to be very, very patient. I've heard from various places that a newly adopted dog (not even abused or particularly "special" circumstances) would take months—like 4-6 months—for them to *really* get settled. Some more quickly and more slowly, for sure, but that might be something to keep in mind. Good luck!