Another power couple on the rocks: Sam Donaldson and Jan Smith Donaldson. The veteran ABC newsman, 78, and his journalist wife of 29 years quietly separated several months ago, her attorney confirmed to us Wednesday. “They remain on good terms with each other and are hopeful they’ll be able to resolve their economic issues,” lawyer Sandy Ain said. No reason given for the split, and the couple has not yet filed for divorce, said Ain: “It’s unclear where this is ultimately headed.”