Harry saved Draco's life twice in the Room of Requirement in the last book (Deathly Hollows) for which Malfoy is grateful. Draco also left the Dark side so he isn't a Death Eater. But they never became chummy with eachother, like Harry and Ron. They simplely don't hate eachother anymore.
The Malfoy family reformed after the Battle of Hogwarts. Even Narcissa and Lucius turned a new leaf, and dropped their blood mania. Draco even more so. They still believe in the superiority of the pure-blood, but in a more passive sort of way, like Slughorn. Draco made a proper pure blood marriage, as was expected of him (and as is common among the upper classes even today, to make 'proper' marriages within ones own class), but he is raising his son, Scorpius, to be much less prejudiced.
Harry and the Malfoys are on cordial terms, but don't associate.