In the pilot, Caroline said that she didn’t want to be shallow; she wants to be “The abyss deep.”
In 7x13, when she’s leaving for NOLA, the song that’s playing is called “The Highest Tide.” The lyrics say that it’s time to try something dangerous and when the water rises, will you keep her safe. As she’s driving towards NOLA, she’s become an ocean. She’s not a kiddie pool that played it safe who couldn’t see life past Mystic Falls and her black and white morality. As she leaves her old life behind, she has opened herself up to the world, possibilities, danger, and a different outlook on moralities.
She has become the person she has always wanted to be and the person Klaus always knew she could be.