I think you are taking the failure personally.
I dont want to appear blunt or undermine your ability and knowledge, but i feel you have a bit of an ego problem. Quotes like "this is embarrasing" wont do your mind any good. We all forget, no one is expected to remember everything in this trade, and to be fair none of us will ever know it all.
The best of the best have failed the 2391, its difficult without enough preparation time. Its down to simple reading and understanding GN3, the terminology is key, and structuring your answers will help. the exam success book is very good.
As others have said GET INVOLVED ask, there are a hell of a lot of top quality sparks in here and between them will know all the answers and will want to help. I am fairly sure i wouldnt have got through 2391 without the help i got in here.
So all I can say, is get up, lick your wounds, eat your humble pie, AND GET STUCK BACK IN.:90:
Cheers...........Howard