I guess with Shae it's like a love-hate relationship. She did love him, but she got clingy and maybe a little jealous when he wasn't around. Being in a situation like that can lead to conflicted emotions that can come off cold and hateful. You also have to consider how powerful Tywin was, she was probably scared he'd punish her if she didn't do as he said.
"Adulthood is like looking both ways before you cross the road, and then getting hit by an airplane" - sarcasm_only
"Ironically like the nativist far-Right, which despises multiculturalism, but benefits from its ideas of difference to scapegoat the other and to promote its own white identity politics; these postmodernists, leftists, feminists and liberals also use multiculturalism, to side with the oppressor, by demanding respect and tolerance for oppression characterised as 'difference', no matter how intolerable." - Maryam Namazie
"Ironically like the nativist far-Right, which despises multiculturalism, but benefits from its ideas of difference to scapegoat the other and to promote its own white identity politics; these postmodernists, leftists, feminists and liberals also use multiculturalism, to side with the oppressor, by demanding respect and tolerance for oppression characterised as 'difference', no matter how intolerable." - Maryam Namazie