She didn't want to give him any further explanation as to why Antonin wasn't there with her when the attack happened. It was part of his plan to do what was necessary to break up her marriage. Just when they were doing so well, he'd been behind the plot to rip the Dolohovs apart. If she told him that his machinations had been successful, he might have found pride in his accomplishments. Besides, she was fairly certain that he already knew it worked after the loud row they'd had in Hogwarts. Of course, Draco probably already told him whatever he wanted to know. Instead of elaborating on her marital status, she continued her story.