TweetI would try to ignore it to not cause a potentially embarrassing situation. However, if the couple gets too bothersome you could ask the husband to step outside and politely ask him to ease up on the interruptions and bogus stories. I suppose this is how I would handle it, but I know it is tough to hold back. If someone crosses the line of intentionally trying to embarrass or insult you, then it would probably be okay to say something even if it does cause a bit of a scene.
Personally, if someone I don't like is going to be somewhere then depending on how bad I don't like being around them I may not show up. If that's the case, I would probably let the hosts know why I wouldn't be making it.