Michelle Fairley, who played Caitlin Stark, said the following during an interview with Entertainment Weekly:
You couldn’t have missed the online furor over the lack of Lady Stoneheart in the Thrones finale. Were you surprised by that attention?
I actually haven’t seen any of that. I don’t look that stuff up. I avoid it like the plague. I was totally unaware.
There was a lot of online conversation. I heard third-hand that you were basically told that it’s not likely to ever happen. Is that accurate?
Yeah, the character’s dead. She’s dead.
Do you have a preference at all—do you think Catelyn’s arc should end where it ended, or would you be into the resurrection idea?
You respect the writers’ decision. I knew the arc, and that was it. They can’t stick to the books 100 percent. It’s impossible—they only have 10 hours per season. They have got to keep it dramatic and exciting, and extraneous stuff along the way gets lost in order to maintain the quality of brilliant show.