this. Garrosh was at Gilneas. That aside, the actions of Sylvannas either under his command or otherwise pretty much rule out any lovey dovey ending to Seige between Horde and Alliance.
I don't think as an Alliance player, in light of everything the Horde have done, that Siege will feel like a victory regardless of outcome.Anyway as for the question, where do Horde-Alliance relations go from here? I suspect that the Alliance and Horde will both be too busy with their own problems to care about eachother for a little while. Eventually they'll be back fighting eachother though, that's what this franchise is about after all. And after an Alliance victory like this I think it only makes sense that the Horde gains some small victories again here and there. Can't have one side feel like the ultimate loser, right? I'm sure Blizzard wouldn't do that to their fans.
Edit: Also, in response to whether Theramore was an atrocity; civilians only got out while Garrosh waited for the Alliance to bring more military forces in. Nothing humanitarian about it, especially when you see that he captured and imprisoned some of those who did escape.