The question I've wonder about, and mentioned too many times - if a flashlight was part of her emergency kit packed by her Dad and if the flashlight was missing.
It seemed she was determined to get to a mountain.
It seemed she headed off east toward the mountains.
Without a flashlight it would have been very difficult to have run far without twisting an ankle.
With a flashlight she could have made it miles away to an area where if she succumbed in the woods she hasn't been found.
Apart from that, the river next to the road - if she thought it was field and fell through ice.
I've always wondered about a flashlight too. It would have made a big difference. I can't see how she would have been able to see her way down the road without one. I know your eyes can adjust, but there is very little ambient light in the area and I believe there was cloud cover, so there was no moon light. She could have used her cell phone to see somewhat. I've used mine to see key holes or items I've dropped on the ground at night. It helps, but it is very limited. I'm sure she probably wanted to preserve the battery. Although, she may not have thought of using the cell phone as a light.
I wonder what the depth range is for that river. I'm sure it varies. Even if it was only waist deep it would have been a problem if she broke through the ice. The cold water would have been brutal. The only thing-- I can't imagine her walking away from the road into a field. She probably wouldn't have seen it anyway, unless she had a flashlight. She could have jumped away from the road, after hearing a car approaching and slipped--hurting herself in the process. If she didn't accept a ride, I figure she may have avoided all vehicles, because she feared they were the police. She could have felt vulnerable too, so she didn't want to be seen by a passing dirtbag. IMO, an accident was possible. Lets face it, it was pitch black, cold, and in an isolated area, especially if she ran east. JMO