I really sympathise and it was a very moving story - but even though you've had denials - as people above said - you still did things differently and enhanced your daughter's education with real experience. I would think there is a great deal of hope that she will adjust - and I can assure you that the Middle School and high school years of my teenage step daugthers were totally different from their childhood. The eldest still got into college on a scholarship and is doing great! I'm sure your daugther will succeed too.
Thanks for sharing your story. As my DS6 just got the ADHD/ ODD diagnosis too for similar behaviors - its interesting to her your story, see how other scenarios have worked out etc.