Sorry to hear you haven't found her.
Sound like she was bleeding pretty steady in spite of teh missign blood near the road. Blood trails are less evident when deer run, and I bet she ran across the road and then started to walk again later on the other side.

It coudl very well be a non-lethal muscle hit (too high maybe?).
I think muscle wounds would start bleeding more after an exertion like running. The dots connect. She may be down, but it may be a long way off.