How long have you been married?
Why would you think this?
How old are the two of you?
The question is, what do you want to do? Do you want to show up at the meeting place and confront them? Do you want to confront him before the dinner and ask him what in the world he is thinking to bring this woman back into your life after what has already happened? Do you think that he's cheated other than that one time? Do yout hink he would risk your relationship again?