...and not only that, doesn't separation mean that you don't have to make a report on your actions to the person you're separated from?
As in, even if he IS seeing the waitress, and hasn't told you, what is actually wrong with that?
This is fruitless. Drop it.
Not only do waitresses flirt and make things pleasant for their patrons, THEY BRING THEM FOOD!!! Unless your husband is a whiz in the kitchen, he's going to get a twinkle in his eye to anyone who's bringing him dinner - he's hungry!!