Even with the words spoken aloud, Hermione didn't know if she could believe them. He wasn't a man that she could easily trust. Hadn't he proven that already? He'd betrayed her to his uncle. Yes, Rodolphus would've likely been able to put the pieces together that Hermione knew something was up with her mind thanks to her husband rushing off to his brother and demanding to know where he was. He was a smart enough wizard to know that the only reason Antonin would be that angry was if he knew what he'd been doing to his wife for so long. But, Draco was the one who actually told him that she was the one who was looking for him. Maybe he didn't realize the significance of his actions. Didn't matter. He'd already proven that he couldn't be trusted.