I've played this over in my head and wonder if he didn't get behind her, in his car, about Boundary and Middle, and was driving slowly, tormenting. catcalling and taunting her. If maybe somehow his car and presence kept "pushing" or guiding her where he wanted her to go without actually touching her with the car.
From the map, it appears to me she might have turned left, up a stretch of deserted road toward her mom's, but if he were behind her, maybe she felt more comfortable staying on 385 because there were a few houses on 385.
I suspect that him being in the area, harassing her might have influenced where she was able to go.
Don't know if that makes any sense . . .