Nancy the checkout girl
While I don't necessarily condone committing adultery I can understand why Phil had the affair with Nancy (which Isn't the point of this post but I thought I'd just state that. In essence because of Nancy's mistake things eventually start to look up for Phil even though they don't seem that way to begin with. Now when I say Nancy's mistake I mean after she had done the pregnancy test and found that it came up blue. But what does she do. She calls Phil at his house only to get the babysitter because he and his wife are at Mitch's house celebrating his friends birthday along with their other pals.
So the babysitter tells Nancy where she is which leads her to make a bee line to Mitch's party. Now, I know she was upset and behaved irrationally but what she did was a bit stupid. She should have at least made an appointment to see her Doctor to confirm her pregnancy before making such a rash decision. At least that way if she wasn't pregnant she wouldn't have gone and wrecked her bosses best friends birthday party. As for the marriage that was already pretty much a over It's just Phil didn't have the nerve to divorce his spoiled, obnoxious wife! But to have Phil's adultery brought out in the open like that was not the way it should have went down! Not in front of whole bunch of other people!
Enough people probably knew what Phils wife was like but never the less! To be a middle aged guy and have it announced in front of every one you've been having an affair with a 20 year old girl. It's got to be pretty humiliating!
She should have waited until she knew for sure and then tell Phil and they could have then decided where to go from there! Either that or tell him her suspicions in private if she felt couldn't handle finding out for sure on her own. That way he could have maybe been there for her. Unfortunately that's not what happened!