May she RIP. Horrible not only for her, but her family, all the witnesses, and of course the train crew.
Looking at the video (I don't recommend without warnings).... it appears as if she did not take into consideration the width-factor of the train, as she was struck by the "elephant ear" smoke deflector.
Another video taken farther down the track doesn't show the impact, but it does show show 844 blasting the horn approaching the crossing, and then realizing what happened, and going into emergency.
Sad all the way around.