The Brothers & Sisters star hit headlines two years ago when he was accused of cheating on his wife Rosetta with the British actress.
The scandal dogged the pair for months and Miller recently admitted she suffered a "semi-breakdown" because of the furore surrounding the doomed love affair.
Getty separated from his partner after his fling with Miller was revealed, but admits they have now reconciled for the sake of their four children.
He tells America's Harper's Bazaar magazine, "Here's the bottom line: It was a very challenging time for everybody involved. But I loved and missed my family too much not to make it work. Rosetta is understanding enough and spiritual enough to let us try."