Ellory was convinced that Antigone was under Tiberius' influence in some way. Either via the curse, or he'd made her swear an Unbreakable Vow to never badmouth him, even if she was confessing to people that he was abusing her.

Ellory had conflicted feelings when Antigone told her that she was too weak to survive childbirth. She wanted to remind her that she had been through the Cruciatus Curse, which caused the worst pain someone could ever experience. It was the Gryffindor pride of hers, that wanted to prove that she would survive whatever Claude put her through.

Antigone gave her another piece of advice, to distract him. "So you're saying that they can control somewhat how painful it is?" She really wanted to cling to the belief that Claude wouldn't do anything to cause her more pain than needed. That he wasn't secretly more similar to his father and Tiberius than he was to Cash.