“I’d never have believed this. . . . The man who taught me to fight dementors—a coward.”
Harry speaks these angry words to Remus Lupin in Chapter Eleven, after Lupin has offered his assistance and protection to Harry on his quest. Lupin has just married Tonks and gotten her pregnant, but he already regrets these actions, foreseeing a future in which his child will be scorned as a part-werewolf. Harry correctly perceives that Lupin is only superficially embracing risk and danger, and is in reality fleeing his responsibilities. Harry is in no mood to be patient with anyone who abandons his child, feeling himself to be painfully bereft, not only of his own parents, but of Sirius and Dumbledore, whose guidance he badly needs. Harry’s outburst is thus a sign of Harry’s own resistance to having to take responsibility for himself, as well as a deserved rebuke to Lupin, and a reminder that the hardest task can be staying loyal and faithful to someone, even when that means doing nothing. Harry is struggling to stay loyal to Dumbledore.