Well, that was a sure-fire why to shock Ted out of his apparent anger. Ted felt his fists unclenching and his eyes bugging out of his head because though he knew that he didn't expect for it to - you know - come up again. He did love Narcissa, of course, but he wasn't in love with her. He was head over heels for her sister and though he felt bad for it he wouldn't have it any other way.
He just wished Narcissa could love him the way he loved her. He wished she had found someone who would treat her nice because they loved her. He wished a lot of seemingly futile things all of them he didn't dare speak. So instead he just stood there, unsure of what he was supposed to be doing.