My DH is the clothes hoarder in our house, so recently I packed away a heap in a space saver vaccuum bag and hid it. He didn't even notice! SO when he didn't go looking for one single thing in that bag, I told him and donated it.
Maybe you could try that. Do what Nelle said and store those clothes away from your wardrobe and your eyes. I bet you find you don't go to them once.
Even though you're worried you are going to be caught out aren't you more likely to make use of what you know fits and is comfy rather than those that don't/aren't?

I would love to go to oneo f those stylists but dollar wise it's a no go. I have been scouring the net though and found the Trinny and Sussannah website really helpful and have been looking at 'capsule' wardrobes.
Like Nelle said you really only need a few key things.
This is especially useful for me as we're about the move interstate, first to one place for 3months whilst our stuff goes into storage. SO I need to only take the amount of stuff you would for a holiday for three months....including all the stuff I might need for the kids.

Good luck - you can do it!!