So I recently deleted You & I, the book that was supposed to finish Simon and Rose's story. I deleted it because there was simply nothing there. It had no plot and it was purely written because I felt pressured into doing it. I didn't want to write it and so i unpublished it. Fixing Her is the official ending to their story, but feel free to dream what you want.
p.s if i were to write more, Simon and Rose would end up together no matter what. So would Cal and Vik - they stay together and get married in my head.