Harry Potter's Archenemy

Reflecting about the archenemy versus nemesis idea, I was thinking of examples from popular culture and the first that came to mind was Harry Potter.
I really loved the Harry Potter books and was thinking of Harry's relationship to Voldemort to help determine and define the differences between Archenemy and Nemesis.
Harry and Voldemort are inextricably linked because of Voldemort's deadly attack on Harry's parents and his attempt to murder Harry himself - the scar on Harry's forehead being an external reminder of this action.  However, to add a counterpoint to my own argument, Harry continues to seek out Voldemort partially to avenge his parent's death and to serve as the agent of retribution by killing Voldemort.  But, to volley the ball to other side fo the court, Harry was regularly told not to think of his mission as one of revenge as that would cloud his thoughts, judgements and ultimately, his heart.
Popping those ideas around, I'd really stick with Voldemore as Harry's archenemy. They are linked by Voldemort's action against Harry's parents and Harry himself.