While the story is true, the movie shows many chances she had to leave. After all, the place was only " 30 ml/ 50 km distance " FROM CIVILIZATION " - that was one of the opening lines in movie.
She had all the supplies she needed. She could have left any time she was ready. It's only 50 -60 km to a nearest phone which is less than 12 hour walk for a trained person or 24 for untrained.
Either way the movie and her story didn't make sense to me.