Princess Catherine was heartbroken when Prince William unexpectedly canceled their Christmas plans in 2006, leading to a brief separation. William's decision, fueled by doubts about their relationship and advice from his family, caused Catherine significant pain. This pivotal moment, detailed in Katie Nicol's book, ultimately strengthened their bond, culminating in William's proposal and their enduring marriage. Let's watch the video to uncover more details of this emotional turning point in their love story.