The RL officer did a wonderful job...I doubt she'd be moping about miserably the way Keeley Hawes did though.
I agree with Jane10 on this.
It's not a criticism of women in general, just that KH isnt as convincing an actress when directed to portray a character in this manner.
Let's be realistic here, the program had to get so many different perspectives across, including the inhumanity of the situation.
The director had to find a way of signalling the support of this particular officer, against the backdrop of the disinterest of the other officers Banaz had met.
Hence the scenes where the character is overcome.
Wonderful actress though KH is normally, she just wasnt that convincing at this.