Ben was sloppy when it came to hiding the affair

When he told his wife about finding Wendy in the Carver's basement with Mikey, how could he not think she would ask him why he was there? I don't condone their affair, or any affair, but you should have a story lined up in case you get asked something like that. Especially since he was the one that brought it up. Maybe the booze clouded his judgment.