Demi-God

I haven't read the book but I was never expecting them to stay completely true to them. There are things that you can do in books that just don't work as well on screen (introducing a load of characters being one of them), but they've done well so far.

As for Stannis, they have another 8 episodes to flesh him out further. I'm already really curious about him from what others have said about him and for how they portrayed him in the last 2 episodes, as someone who gets a ton of respect from those around him but also seems to be unhinged somewhat.

And he doesn't really just screw Melisandre out of the blue, she promises him a damn son, something his wife seems to be failing to give him, there was a reason it happened.

This won't ever be like the books, nor will it somehow taint the books by changing things. Just treat it as its own thing and enjoy it for what it is, hell George R. R. Martin is actually writing the episodes too so you have to put a little faith in him and know that he's doing what he can to make sure he transfers his work over a best as possible.