My memory is so terrible that I dare not tell even white lies, so I am forced to tell the truth, preferably in a way that preserves the requester's dignity, not

My memory is so terrible that I dare not tell even white lies, so I am forced to tell the truth, preferably in a way that preserves the requester's dignity, not just a blunt "no." The truth is usually along the lines of "Sorry, I would like to be able to help, but I have too much on my plate right now and more keeps being added to it every day."