When you have so many email, Facebook, etc threads going that if someone doesn't include your previous email/FB message in their reply you can't remember what the subject was about.
Charles to Camilla on 01 April 2008:
"Oh Camilla, I do love those English thighs of yours!"

Camilla to Charles on 27th August 2008 (not including original message):

"Oh Charles, they love you too!"

Charles to Camilla on 14th November 2008:

"Huh? Wot R U talking about - I have Threadnesia"

NOTE: They don't FB much...
by Miss Hairpin April 10, 2008
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