Hi skyborn! First of all, you're NOT pathetic - you're human like the rest of us! My suggestion is to always have a glass of ice water in your hands. Load up on that and there won't be so much room for snacks. And when you're not drinking, hold the glass with both hands so you don't have a free hand to reach for the snacks. But if you DO reach for them - there's almost always a veggie tray - stay near that, but don't go overboard on the dip. Also, maybe you could try to imagine that every time you reach for a snack, everyone at the party is watching you!
Then you'll be too paranoid to eat!
But like you said, do let yourself have just a small taste of the good stuff. But not every single thing - pick one or two things that look the best, and have a really small amount. Then chug more water!
Hope this helps. Have a blast at the party!
"If there are no [mastiffs] in Heaven, then when I die I want to go where they went."
- Will Rogers