My guess: Even though ambassdorial duties in a little state like Luxemburg have got to be rather trivial, I'd say this appointee was too lazy to even go through the motions of doing her job - she probably expected everyone else to do her job for her, and when that didn't happen, she began berating her subordinates.
Drunk with power or her own self-importance, she went ahead and treated herself to all kinds of goodies without any attempt at discretion . . . and essentially flaunted her bad behavior.
The staff she alienated, rather than cover for a poltical hack they detested, simply let her behave that way until things caught up with her.