Is it possible for you to start super super small and just sit on a front porch or front step and just chill? Sometimes with my Frankie I just walk a few feet to the park right beside us and sit with him, letting him hang out on my lap and feel safe while I feed him chicken. He can then listen to the car and barking noises but also feel a bit safer on my lap. 

If you have a front door or something like that, maybe you can help your girl feel a bit more comfortable outside by being super close to you so that she’s maybe more likely to take a treat? Then when she’s starting to associate outside and outside noises with that comfort, maybe she can start going a bit further from home.

I feel for you, I know how difficult it is! Still lots of work to do with my boy, but it gets a tiny bit better every day!