No, I don't see it ending badly- I'm sure that no matter which route she takes, there will be people critisizing her decision.
I mean, Stephen King even flew to England to ask her not to kill Harry in the last book. As if he had any say in who's characters get killed.
I think it would be a good end to the story- but at least one major character has to die- either Harry or Voldemort have to kick the bucket, and I think it's possible that they're connected somehow, so both of them will die if either one has to.
I think that's the direction things are going.
-kv