This was my problem with the books! Tyrion murders his girlfriend, a character I like, and then is off whining about some girl who's not a character in the books whom he was married to for two weeks many years ago. He's like "oh, Tysha, Tysha," and I'm all "The hell with Tysha, what about Shae, you asshole? Die!" and I lost all sympathy for him. I really, really hope they don't go with that scene the same way on the TV show, because I felt like it was a major misstep in the books. GRRM has said he wants to make Tyrion a morally neutral character as opposed to a "goodguy" or "badguy," but killing Shae just made him irredeemably bad. It's the whole horrible "disposable sex worker" thing, I guess. I stopped watching True Blood after they had Bill procure a stripper to kill, I think it was partway into the 3rd season. I had read the books, and the book character would never do anything like that. And the show tried to make it "okay" by having him determine that she was just a sex worker, with no family. In other words, not a real person with value. But sex workers are people too, and killing one is no less wrong than killing a bank teller or social worker or UPS delivery guy. And my hatred for the character I'm supposed to forgive only increases the more the show tries to tell me the victim was worthless. Shae has no power and her life is in danger. What the hell is she supposed to do, be bravely tortured to death defending her man? F*** that. And f*** book Tyrion too. The show has a chance to do better.
A couple things...
Tyrion didn't kill Shae because he was a sex worker, he killed her because he felt monsterously betrayed by her. It doesn't excuse the murder, but it was definitely a crime of passion, not a murder because he felt she was "worthless".
IMO, after he kills Shae and Tywin, Tyrion is in a psychological state of severe depression. He fixates on Tysha specifically because of Jaime's revelation about how he was complicit in their meeting and in Tywin's cover-up about it, and because she becomes a stand-in for Shae in his thoughts. If you read the sample Tyrion chapter from TWoW available on the World of Ice & Fire app
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