Regarding the first letter in "Annie's Mailbox":
http://www.creators.com/advice/annies-mailbox/choose-your-battles.html
Your thoughts?
I've found the best way to deal with these sorts of control issues is to act as if they don't matter. So if the lady goes to the party alone she should be the life and soul, charm the pants off everybody there, talk about how wonderful her new man is and how happy she is and how he was just too busy with work/his own kids/building his yacht/whatever to have come along. I'd really ham it up; I find nothing annoys them more than realising what they think and what they do doesn't matter 
Thanks, Tupp.
I would advise the lady that if it were me, and my ex attempted to control me with the crapola of "Do as I say, NOT as I DO", I would simply show up WITH my current love, say "Hello" to the ex's current girlfriend, who is also attending, and enjoy myself at the party while IGNORING EX.