I thought Rhode had a lot of potential to be a conflicted rival/friend/reluctant enemy. Stuck between her code of conduct, responsibilities and her personal investment in your character.
I was disappointed when the writers tossed this excellent opportunity out the window and she just turned on you without any hesitation. Perhaps a little remorse, but she wasn't conflicted at all and didn't even entertain sparing you as an option.
Real human beings just don't behave that way, in such frigid absolutes.
The Dragon Slayers are almost a military organization. In a war situation, a commanding officer would not hesitate to give the order to execute a soldier found guilty of treason.