Oh my gosh! Twelve people coming to dinner...I'd be a wreck! I've never cooked a whole turkey either!
I am the queen of deception. I have great serving bowls, platters, elevated stands, etc. I buy restaurant food and dish it into my serving wear and keep things warm in the oven until company arrives. (This works especially great for out of town guests that dont know your local restaurants.

) To make it convincing i put saucepans in soapy water in my sink or load some in the dishwasher, along with wooden spoons, spatulas, etc, so it looks like ive been busy cooking. Put the restaurant wrappers in your outside garbage can, NOT your kitchen can (I've been busted before.. )
You're not a failure! For those of us that don't excel culinary, the appliances are always the problem! When they are old "they don't work well anymore" and when they are new, "they don't make them like they used to."
Now find a cracker barrel! Or, by me, our local grocery stores also allow you to order complete Thanksgiving dinners, so check yours. Ive bought full dinners from Meijer before and it was delish!