Eddard Stark. Robert Baratheon. King Joffrey... Just some of the dearly departed George RR Martin killed off, seemingly at the drop of a hat. But why does he continously dispatch viewers' favourites? 

In an interview with Galaxy’s Edge, the writer had this response to the questions "How do you use death in your writing?"

His response was lengthy. Here's the main points: "I don’t think of it in those terms, that I’m using death for any purpose. I think a writer, even a fantasy writer, has an obligation to tell the truth and the truth is, as we say in Game of Thrones, all men must die. Particularly if you’re writing about war, which is certainly a central subject in Game of Thrones... If you want to be honest [death] should affect your main characters... They go into battle and their best friend dies or they get horribly wounded. They lose their leg or death comes at them unexpectedly."

As for death in general... well, it's part of life, innit? We're all going to die - irrespective of how popular or cute we happen to be: "Death is so arbitrary. It’s always there. It’s coming for all of us. We’re all going to die. I’m going to die. You’re going to die. […] You don’t get to live forever just because you are a cute kid or the hero’s best friend or the hero. Sometimes the hero dies, at least in my books. I love all my characters so it’s always hard to kill them but I know it has to be done. I tend to think I don’t kill them. The other characters kill ‘em. I shift off all blame from myself."

So, that's how he lives with himself.