OMG I do too! And with me being a gay guy it's really not how I want to feel. I'm not hating on drag queens btw I'm just saying. And I also second getting a pant suit. Perhaps something like this:
Macy's- Calvin Klein Suit, Two Button Jacket & Pants
(The gray is a little less masculine then black and your mom might go for it. Or maybe even a white suit?)
With this top underneath:
Macy's- Rachel Rachel Roy Blouse, Compartment
(I know the top is kinda femme but I was thinking your Mom might got better for the suit if you get a femme top. And if you don't take off your suit jacket no one will really know how femme the shirt is.)
And for shoes:
Macy's- Hush Puppies Shoes, Huron St. Loafers
(Which I know isn't very stylish but it is pretty gender neutral.)
or
Macy's- Easy Spirit Shoes, Divine Booties
(Which does have a bit of a heel but a more masculine cut to it.)
I just gave you suggestions from Macy's which can be a little overpriced sometimes, but you can find comporable stuff at JC Penny's, Kohls, etc.
Anyway I hope I helped. And have fun at the party!