I like your story but... Ron is really bothering me. Ron can be a git, and he's not my favorite character to begin with, but this Ron is just wrong. The times when Ron has turned on Harry, it's been about Ron--Ron is jealous of Harry, Ron is hungry and feeling sorry for himself--it's always about Ron. He can be immature and self-centered. But the Ron in your story is mean and vindicative and that doesn't ring true. You can still have Ron be a git about everything--I know you want to emphasize the isolation angle--but to keep it in-character, you'll need to find a way to make it about Ron, and not just about "Slytherins" (Perhaps Ron is feeling slighted that Harry accompanied the Malfoys and not the Weasleys, or that Harry is too good for his friends/the Gryffindors because his father is a Professor/Head of Slytherin). Anyways, I hope you don't mind the constructive criticism. I can't wait to see where the story goes and what chamges Snape's mind.
Author's Response: In my mind Ron is upset because he believes Harry has switched sides. Previously it's been him and Harry against the Slytherins and against the world. Now Harry is uncertain and that bothered Ron enough to push him over the edge. But since Harry and Ron aren't talking, and Hermione and Ginny are also sort of out of the picture, Harry doesn't know this, and neither does the reader, at least not yet. Sorry it bothered you that much, but it bothered Harry that much too and I wanted the reader to be upset by it.
Thanks for the review. Constructive criticism is of course always welcome so I definitely don't mind. I always look for ways to make my writing better.