I use vetericyn spray for wounds, it works very good. If you can get the VF formula, Veternarian Formula, its double the strength as the one at a feed store.If I had to guess, I'd say a bear. A mountain lion would jump over your fence, a bear would come through it, tearing it off the posts or whatever. Oh my gosh... please don't assume she can't make it. Clean the wounds really well, if you have iodine, clean them several times a day but don't bandage, they need to be able drain. If she has torn skin, it would be better for her if you trim the wounds so they have clean edges... they'll heal better. You can use human antibiotic ointment on her too but trim her feathers away so they don't stick to her wounds. Bring her in and keep her warm so she doesn't go into shock and then freeze tonight. I know its late there already but I'm hoping you've done this part, or that you will be getting online late tonight.
Blueberries have natural aspirin in them if you have any in your freezer. Chop some up because they don't like the dark outside of the berry but the lighter inside invites them to try them.
As she is severely stressed, feed her some plain, unsweetened yogurt. It's a situation like this that will allow the bad bacteria in her intestines to get a good foothold on her and she'll be fighting a losing battle.
Keep us posted ok? Maybe we can get her pulled through.
I wass also thinking bear too when you said the fence was torn down