The David Brent syndrome by Marc Abrahams:
Overall, the results showed that incompetence is
even worse than it appears to be, and forms a sort of unholy trinity
of cluelessness. The incompetent don't perform up to speed;
don't recognise their lack of competence; and don't even
recognise the competence of other people.
How to Deal With Impossible People:
Realize that you cannot deal with impossible people
the same way you deal with everyone else. In some ways,
they need to be treated like children. Give up all hope
of engaging these folks in any kind of reasonable conversation.
It will never happen, at least with you. Remember what happened
the last fifty times you tried to have a civilized discussion
about the status of your relationship with this person.
Chances are, every such attempt ended in you being blamed
for everything. Decide now to quit banging your head against a brick wall.