BURLINGTON, Vt. — Maintaining one’s own space after moving in together can be tricky for a couple, especially if they are artists of a certain age, set in their ways. This was the case with Eleanor Lanahan, a 63-year-old filmmaker, writer and illustrator known as Bobbie, and John Douglas, a 73-year-old filmmaker and political activist.

Lanahan smokes; Douglas does not. She likes pretty, traditional furnishings, while he is all about simplicity and comfort. She cares about architecture; one of Douglas’ suggestions, as they were trying to figure out their living arrangement, was that she put up a big billboard of whatever kind of house she wanted — say, something with a big old gambrel roof — and they live in an old galvanized shed behind it.

They shuttled, for 18 years, between his cabin in Charlotte, Vt., overlooking Lake Champlain, and her three-story house in Burlington some 30 minutes away, never able to agree on a home they could share. Finally, skyrocketing taxes forced Douglas to give up his place. Lanahan’s house had a rental apartment, and Douglas might have easily moved into that.

Instead, they built a separate studio for Douglas, with two bedrooms and a bathroom, that is connected to Lanahan’s house with a bridge: a 20-foot plant-filled overpass. The cost of the addition was about $366,000.

Douglas plays the music he likes in his space; Lanahan plays what she likes in hers. They eat and sleep in Lanahan’s house and watch the news after dinner in her living room, but tend to watch movies in his space. During the day, they often communicate by phone.

There were a number of factors that led to this unusual arrangement, but high on the list was the need for a room of one’s own.

“We definitely wanted independent space,” Lanahan said. “He could have had the apartment. That would have connected us completely. We could have opened up a wall. I think he just wanted a place that was a lot like the one he was leaving, and his own domain. This is so similar to what he had in the country, it’s phenomenal. We built the studio to be just like his big room, minus the wall he used for a kitchen.”

Douglas, who wears a ponytail and has an unsettling resemblance to the actor Nick Nolte, disputes this. This place is not an exact replica, he says. The furniture is not precisely where it used to be. But yes, he admits, he did not buy any new furniture, and it is very similar. He also says that many seem to covet their bridge.

“When it was built, so many people would say: ‘I wish we had a house like this. It would be so great,’” Douglas said.

“Of course, you wouldn’t be able to keep as sharp an eye on your mate,” Lanahan added. “If you were having a horrible relationship, you do have your own entrance.”

When you meet a couple who have dated for 18 years and moved in together only because of outside circumstances, it is difficult not to engage in a little amateur psychology. Douglas grew up in a prosperous family in Lake Forest, Ill., and his mother died when he was 10. He was, he says, brought up by nannies and sent to boarding schools. He has a son and a daughter by two different women, neither of whom he married.

“I couldn’t imagine why you’d get married,” he said, when asked about this. “I had no family experience.”

‘Naked things’

A politically conscious filmmaker, he made a movie about black farmworkers called “Strike City” in 1966 and a documentary on North Vietnam in 1970. His 1975 film, “Milestones,” about the 1960s generation, was shown at the Cannes and New York film festivals.

At times, work came before family: Douglas told the website Jump Cut that while he was editing “Milestones” in New York, he had ignored (or, as he put it, “rejected”) his 1-year-old son in Vermont. But in later years, he moved to Vermont, and his son and his daughter often lived with him.

The political activism-through-art continued. His anti-war, anti-killing site, the Homeland Security Collection, offers a playful series of images of the naked Douglas posing with an M-16 assault rifle.

Why is he naked?

“I was trying to put the weapon in a context that made it ridiculous,” Douglas said. “You put on clothes — you are suddenly one of them.”

Lanahan, whose mother, Frances, was the only child of F. Scott Fitzgerald and his wife, Zelda, had been a Washington debutante and studied art at the Rhode Island School of Design. She married at 24, in 1972, had twin sons and a daughter and was divorced in 1988.

In her 1995 biography of her mother, “SCOTTIE The Daughter of … : The Life of Frances Scott Fitzgerald Lanahan Smith,” Lanahan writes about her own marriage, saying that her husband cheated on her with a stepsister and a baby-sitter. Her award-winning animated short film, “The Naked Hitchhiker,” made in 2007, is about a woman suffering from a broken heart after her husband has an affair. It opens with a naked woman.

“Here’s a feeling filter, just so I don’t show any anger or jealousy,” the brokenhearted woman said. “It provides a positive attitude.”

These days, Lanahan does not want to endanger her mended relationships by talking about the problems in her marriage. She will say that the minister who performed the wedding recommended a book on open marriage during the ceremony (hey, it was the 1970s) and that late in her marriage, she had an affair herself. She is also guarded about discussing “The Naked Hitchhiker,” in which the protagonist tells her story to a sensitive and insightful truck driver, who, like Douglas, has a ponytail. Douglas supplied the truck driver’s voice.

Was the film autobio- graphical?

“As an artist, you use your feelings,” Lanahan said. Then, a quick aside: “John was a huge help on this movie.”

Douglas takes up the thread.

“You know what’s kind of weird?” Douglas says. “It had not occurred to us that we both had been working on these naked things.”

Why is the woman in Lanahan’s movie naked?

“She is basically just stripped of everything,” Lanahan said. “It’s an aloneness, an emphasis on the aloneness. Clothes are another layer of protection she just doesn’t have.”

Living ‘together’

Lanahan and Douglas met in 1991. Douglas was living in a simple house on a 20-acre lakefront property he had bought in 1983 for $110,000. One open room included his studio, living room, bedroom and kitchen, with sliding glass doors that looked out onto the lake. On the side was a bathroom and two small bedrooms, which Douglas added for his son and his daughter, who sometimes lived with him. And, at the insistence of a former girlfriend, he had added a second-floor master bedroom in which the mattress was on the floor.

At the time she met Douglas, Lanahan was still in the home she had lived in with her husband and their three children. When the two were together, most of their time was spent at his place.

Sitting in her somewhat prim living room with its family heirlooms, they both get nostalgic about the house.

“It was very simple,” Lanahan said. “It was perfectly comfortable. It had a big wood stove —”

“There was no siren,” asid Douglas, who is irked by the sounds of Burlington city life. “We used to wake up and put the bed —”

“The mattress,” Lanahan corrects.

“We would put it in front of the window,” Douglas said. “And just look at the eagles and the shagbark hickory.” (That’s a type of tree, for you city folks.)

They discussed altering the house so that Lanahan might move in but could never agree on an architectural solution.

Lanahan had the idea of adding a wing that would have covered up the skylight in Douglas’ kitchen, which still irks him.

“We had 20 acres to live with,” he said. “There’s no reason to build over the center of my life and flatten it out.”

Lanahan acknowledges another problem. “I am not a country girl,” she said. “I do a lot of things in town that are easy to do because of time, meet somebody for lunch, do an errand, see a movie. Everything is a project when you live outside of town.”

They also had basic differences about how to use his space.

“The thing that was hard for me to deal with was to build a home for all the children who weren’t living there anymore,” Douglas said. “It was creating a space I considered excessive for that footprint in the woods.”

Two years ago, Douglas’ property was assessed at $1.3 million. His taxes were close to $30,000. He could no longer afford to live on the lake. Selling Lanahan’s three-story house and buying another house together was not an appealing idea: her house was on a large lot, and it would have been difficult to find an equivalent amount of space. They considered adding onto the main house, but that would have meant diverting the driveway.

And so, working with Bob Duncan, an architect with the Burlington firm Duncan-Wisniewski, the couple came up with the bridge house. It is built in such a way that the bridge might one day be removed and, with the addition of a kitchen, it could function as two separate houses — the smaller one being the sort of house Lanahan says she might want if she eventually found herself an elderly lady on her own.

It remains Lanahan’s property, but Douglas has made what he calls a considerable financial contribution.

If the bridge suggests an ambivalence about commitment, the couple insists that is not the case: Douglas, who has changed his mind about marriage, finally proposed to Lanahan.

What happened?

“She said, ‘Not now,’” he said.

When was this?

“A few years ago,” Lanahan said. “We got very close. When you have five children and you aren’t planning on having more children, it’s much simpler not to marry. “

But they feel as if they are married, Douglas says, and they’ve done living wills that give each of them the power to make medical decisions for the other, and stuff like that. Their separate places just allow them their own creative space.

And if Lanahan ever decides to sell the place as is, a real estate agent has assured her that there would be no problem. There are lots of dysfunctional families out there who would love it.