I'm very, very sorry to hear that. Newcastle's is very virulent, and very contagious.
If she has Newcastle's, you need to euthanize your entire flock. If you have chickens or other fowl, those too. I can't stress enough that it is very serious and very contagious. If it gets reported, they will all be euthanized whether you want them to be or not.
Do NOT sell, trade, or transfer any of your birds to anyone else. The last outbreak that I knew of in southern CA took about two years before anyone was allowed to export or bring birds in.
Apparently you need to report it as well.
https://www.aphis.usda.gov/publications/animal_health/fs-vnd.pdf