Island of Nightmares

A 15 year old girl by the name of Anna and her family were on a boat trip, they took a public boat that held hundreds of people. Everything was going fine until the boat started to sink, her family including her 5 year old sister Belle died along with hundreds of other people. Anna was fortunate enough to come out alive. She definitely wasn't fortunate for where she ended up. On an island, a dark, cold and dreary island. She was walking along and there was writing in the sand and it read, "Welcome to The Island of Nightmares, where all your nightmares come to life. Enjoy your stay, because you're not leaving... Ever." What does she do? Does she get out?