what did jules really say in that bedroom scene with ben?

In discussing marriage, when Jules says to Ben -- according the audio and the captions -- "My husband is cheating on me," that's NOT what she's saying in synchronization with her lip movement. Clearly the original line in the scene was looped over. What I can't figure out is, what was the original line? I'm not a lip reader, so I'm asking someone out there who might know the answer. And a related question: assuming the original line was one that might be naturally said in context, why was the decision made to overdub it?