His Dragon Queen

She had so much power and she didn't even know it when she left her small town of Mystic Falls and came back to her hometown of Forks something changed while she was gone for ten years and she went for that nice girl to the cold heart one who just wanted to be alone but when she meets the man she was going to be with forever she changed she had hope again.
What happened to her for the past ten years?
Who will she meet and fall in love with?
Why is she back in Forks?
What power does she have and how did she get it."