A part of what makes the Harry Potter series so wonderful is not just the growth and development of the main character, but of the surrounding characters as well. Throughout each book, the characters find themselves surrounded by choices, and as each choice is made they grow respectively.
Harry Potter is, of course, a prime example of this, going from a boy who loves adventure, to a teen who just wants a normal life, and finally reaching manhood, where he accepts his future and all of the trials and tribulation that it may carry. Despite the overwhelming support of Harrys growth and development, he is not the only one to have felt major changes. J.K. Rowling does her best to support this through the use of Harrys nemesis, Draco Malfoy.
Malfoy had been an enemy of Harrys since they first arrived on the Hogwart's Express. He was rich, strong, and an excellent flier. Though Harry did not realize it, he also possessed those same qualities. However, Draco chose to embellish himself in luxuries, while Harry often stated that he would willingly share all of his money. In every duel save one, Malfoy and Harry proved equal in magical abilities, but due to an external force were not allowed to finish properly. It was a close call every time to determine the winner. In the one duel they were allowed to finish, Malfoy came out on top. The relevance of this can be debated because Harry was caught off guard, but he still managed to strike Harry with a powerful spell at the right time.
Malfoy has also changed in personality. Many of his traits are still prominent, his arrogance, swagger and pride. But as the series has progressed, we see that Malfoy has become more secretive as he delves deeper and deeper into Voldemorts plans. He is now a member of something crucial, the Death Eaters. For the first time in Malfoys life, he finds that he is no longer the biggest bully in the ring. But most noticeably, Malfoy no longer seems to relate to Harry.
A big part of Malfoys life used to be tormenting Harry. Whether about his family, choice in friends, or the hot topic of Harrys life at the moment, Malfoy has always made sure to torment him about it. As he grows more concerned with his own task, the murder of Dumbledore as well as a way to sneak the Death Eaters into the castle, he's stopped pestering Harry. Harry cannot pull away from Malfoy as easily as Malfoy seems to have pulled away from him. Malfoy was his equal and opposite force, it kept his life in balance. It appears that in this sense, Malfoy has matured faster than Harry.
But beyond all of this, all of the emotional and physical changes the two boys go through, we realize something else: while leading completely different lives, they were also leading parallel ones. Harry has known since the end of his fifth year that the task of killing Voldemort falls to him alone, because Voldemort has made it this way. Malfoy learns, probably a few weeks later, that it has become his task to kill Dumbledore. Voldemort has, once again, made this arrangement. Both are charged with killing the two most powerful wizards of the time, a seemingly impossible task. They find themselves in parallel circumstances.
What separates the two of them, what leads us to understand how truly different these characters are, is how they handle these situations. Harry explains what is happening to his friends, he lets them in. He accepts extra lessons from Dumbledore, ready to take all the assistance he can get. He does not hide in corners, nor does he retreat emotionally from those around him. Instead, he dates Ginny Weasley, making himself more emotionally available than he had ever been previously.
Malfoy, in contrast, only ever hints at what he might be doing to his friends, and even then it is nothing more than a maybe I am, maybe I'm not. He doesn't allow anyone in to his now sealed heart, which does help perform Occlumency, but gives him no other benefits. Snape offers to help Malfoy, and he readily declines. Someone older and far more powerful than Malfoy reaches out his hand and he slaps it away. Unlike Harry, he denies help. While his excuse initially makes us believe that Malfoy wants all the glory to himself, a far more likely answer is that accepting help and allowing someone else in will make everything real for Malfoy in a way that nothing else could. He will not be alone, and there will be no waking up from such a terrible nightmare.
The future of the series is dependent upon the relationship between Harry and Malfoy. He has been there since Harrys first true introduction to the Wizarding world, when they met during Harrys very first visit to Diagon Alley. The seventh book could lead to two very distinct possibilities. The first is that Malfoy remains Harrys parallel. As Harry searches for the Horcruxes, discovering all that he can about Voldemort, it is possible that Malfoy will go on his own journey. If this is the case, it would not be a physical journey, but a journey of self discovery. Malfoy would have to reconsider himself, after having such a psychologically trying year.
But there is another, more unfocused possibility. Harry and Malfoy might break their cycle and no longer lead parallel lives. Malfoy could retreat into hiding, evading the battle, certain torture, and possible death. As he does this, Harry forces himself to come ever closer to the same things, and run towards Voldemort, while Malfoy runs away.
Whatever happens, Harrys path seems to have only one outcome, while Malfoy could choose to continue on the one which he currently stands, or he could turn. Then the question becomes: will their parallel journeys continue on?