i'm going to go with a no on this one. I'm going to try the best i can without sounding like i dont know anything, which i dont really.

i believe that there are nerves or whatever in your brain that records your memory and whatnot. The only way to perminatneyly(yeah way off i know) forget a memory is to either destroy that nerve or severely damage it. Now you can't go and decide that you want your body to destroy those nerves and the only way to get rid of them is using some external influence(i.e banging head, pills, pixie dust etc.). so thats why you can't just "want" to forget that memory for forever