It's true - and necessary - that Book 2: The Key begins much the same way that Book 1: The Cage ends.
For those who found the end of The Cage more than they wished to deal with (and based on the voting that was a fair number of you), don't worry. The Key is, ultimately, a story about redemption and healing. It won't be quick, nor will it be easy, and all of Éowyn's emotions coming out of that experience will continue to be part of her. But the end of the first book is, by a very large margin, the darkest this tale will ever get.