I think she is.
I find Katie really annoying....even when she gets told that she looks like Aubreys little lap dog the first thing she does is go running straight back to Aubrey to tell her....
I find her very passive aggressive and fake.
I've seen her show no remorse that her tears and reaction to Biggins resulted in him being thrown out.
I also remember that her tears also were the reason for the only time Ricky lost his temper.
Sly and Disingenouos IMO