What is the name of this personality disorder?

[scarlettckcs]

A person responds to everything another individual says with "I was just going to say that" or " I did the same thing" or on and on and on. It is actually getting weird because there is nothing anyone does or says that this person hasn't already said or done.  It is disrupting to the office and to morale. " Single White Female"  is now the code name for this individual.  What is this ailment and how do we handle it?