What happened at the dinner table?

While with their guests at dinner, the Count demanded that his wife swear that what she had previously told him was true.... that she's had an affair, and that one of his children was fathered by another man. The atmosphere was filled with tension, the Count knocked over a wine glass, and his wife said she had told him the truth, after which, he three down his napkin and stormed out of the dining room. The Comtesse then proceeded to speak with her children and guests as if nothing out of the ordinary had happened.