Welcome to "Mad Arcana", where we find connections between the characters of Mad Men and the Major Arcana of the Tarot. Because symbolism, that's why.
"It's your life. You don't know how long it's gonna last, but you know it doesn't end well. You've gotta move forward... as soon as you can figure out what that means."
The man known as Don Draper is a cypher. This is a man that keeps his personal life so private that not even his family really knows who he is. Born Dick Whitman, he assumed his current identity while serving in the Korean War. After an accidental explosion claimed the life of his commanding officer, the former Pvt. Whitman switched his dogtags with those of the deceased, faking his death and stepping into the life of Lt. Donald Francis Draper.
In his role as Creative Director at Sterling Cooper & Partners, Don is legendary as the master of the pitch. His name is one of the big selling points to potential clients in the early seasons of the show, and he racks up a number of awards and accolades for his work over the course of the series. His creativity, deception, talent for manipulation, and need for complete control in multiple aspects of his life are all reflections of card Number I: The Magician.
Transformation is one of the keywords for this card, and Don embodies it in a number of ways. There is, of course, the obvious—his transformation from poor, son-of-a-whore Dick Whitman into the upper-middle class, successful Don Draper. There's also the aspect of his creative ability, transforming ideas into advertising campaigns. He also acts as a transformative catalyst for Peggy Olson—boosting her from secretary to copywriter, and becoming her mentor in the process.
The Magician, at his worst, has been likened to a used-car salesman (a job Don has held, incidentally); manipulative, deceitful, and shady. Unfortunately, Don embodies these characteristics, as well. He can be charming and affable, but more often than not, he's using his talents (and copious amounts of charisma) to do things not entirely above board. His desertion is one example; there's also the case of his employment at Sterling Cooper (got Roger drunk one night and told him he'd given Don a job the next morning), his multiple affairs, and all the lies he tells to maintain his various covers. He's also a control freak, and gets angry when he feels he doesn't have the upper hand in any given situation. This has played out more than a few times in the course of his relationships (with women especially), and his behavior tends to strain them to their breaking points.
Season 6 in general has seen Don in decline, stuck in his old patterns with no real signs of change. As a result, he's managed to destroy most to all of his relationships with the people in his life. The power of transformation is something Don knows well, however, and only time will tell if he manages to make the necessary changes in his life, so that he can begin anew once more.