Why do the British have such devotion to the monarchy?

I know someone who is an absolute zealot when it comes to the monarchy. To her, they could do no wrong. You mention all the scandals that they have created over the centuries, and she would come up with her cookie-cutter excuses. She even became pissed off when it was decided that a new citizen of Canada could now choose to pledge their oaths to the Canadian flag, instead of to the queen. So why do the British so revere these people?