Haven't read the rest of the posts, but...
You seemed to of found the root of the problem that she is now healed from, but won't get on her to see if that was really it?!?!?
She seems to be telling you she feels better. I would do some groundwork with her and then hop on her at least once. I bet you anything each one of those times that her actions came out of no where to you, it was not out of nowhere to her. The bit must of hit her wolf teeth which you have established were clearly causing her pain.
I am sorry, but labeling a horse unridable after finding a clear source of a reason for her action is just weird.
Get on the horse and ride it before you decide that and unfairly label her. Or find someone with the balls to get on her!