sometimes it helps to scroll the screen down and just watch the shadow, and give it a few dozen rotations and try to time bringing the screen back up so she is coming from the opposite direction...

If that makes sense. Like the part where her back would be to you in your imagination, try to scroll up as she's starting that rotation, since your mind likes to start with the front, as it passes by you'll think, oh it's her front,, and she'll be turning the other way.