If I was you, I’d record her when she’s badmouthing about you, with all the galis and spices. Put it on youtube and send the link through email to all her students and to all those who think that she’s pious.
Throw the party anyways, and take snaps of how fun the party was and send it by mms to her.
Enough to make her furious but at least she’d get the fact that you ain’t submitted to her.