Sometimes you can just say no. Sometimes getting out of the party is...entirely possible. And sometimes it's an unassailable and inexorable Charybdis of a party, where you know you'll never make it out alive. You slip up, give two excuses, and before you know it your fictions are suddenly full of holes and you're in a "going-out shirt" on the way to the store to buy a bottle of Beaujolais Nouveau. Now all you have is a bad attitude.
Finally, there's something to express how you feel while maintaining a party-like disposition: Abusive Balloons.
With slogans like "THIS PARTY IS S***" AND "HAPPY F***ING WHATEVER," Abusive Balloons let you be brutally honest under the careful disguise of humor.