Question about Last Sacrifice by Richelle Mead?

I hope she gives Adrian a happy ending. He deserves it. Also, I don't really understand how Rose can be happy at the end. Sure, she has Dimitri but she practically ruined Lissa, Sydney, Adrian, Jailbait, and Christian's lives and views on life. She lost her bond with Lissa who is now rather going to spiral into depression and madness or never use her powers again. How is this a happy ending? I still love the series though.