Complex sentence: She says that she had been happiest when with his dad and her sons and that he should continue to work hard at his apprenticeship in order to one day hunt the dark rather than be hunted by it.
Split into simpler sentences: She says that she had been happiest when with his dad and her sons and that he should continue to work hard at his apprenticeship. She wants him to one day hunt the dark, not be hunted by it.