"Once you get yourself stable, then you're able to reach out again," Travolta, 55, told PEOPLE. "And I think this whole year, every day we've been working on stabilizing ourselves. And it's been successful so far."
Added Preston: "It helps to look out and be helpful to other people … that really helps."
On Thursday, the couple were at New York's Ziegfeld Theatre for the premiere of From Paris With Love, a fast-paced thriller in which Travolta plays an FBI agent out to stop a terrorist attack.
On Friday, at a press gathering for his movie, Travolta told PEOPLE: "It's been a rough year. I'm not going to say it's not been bad, but we've been working very hard every day at healing … We've worked with our church and we've worked with each other and our friends and our family. It's been a tough one, and it's going to be, but at least we have help and it's working."
Thursday's red-carpet appearance came on the heels of their visit to Haiti, which they coordinated with the Church of Scientology (both are members) to bring 80 medics, 33 volunteers, supplies and seven tons of food, including 4,000 ready-to-eat meals, to the stricken island nation.
Up Close and Personal with FansThe couple said the personal moments – like meeting a 7-year-old boy who lost his family – were especially touching. "All he wanted to do was see inside the plane," Travolta said.
Travolta piloted his own plane and said he's encouraging others, especially plane owners, to offer their own relief efforts. "I'm investigating all the contacts I have to send more support," he said. "You want to get these people planes that other people have that you know of."
Referring to Travolta's efforts in Haiti and elsewhere, the actor's From Paris director Pierre Morel described his star a "beautiful human being. Very, very patient ... The first week after we started, he knew everybody in the crew by name. He was wonderful."
Costar Jonathan Rhys-Meyers added that while it was initially "jarring" to work with an actor he idolized from Saturday Night Fever and Pulp Fiction, the two became "incredibly close" during filming: "He's such a nice guy and he's so sweet that immediately, you forget that you're working with John Travolta."
With additional reporting by PAUL CHI