Waiting for his COVID-19 test results, Stephen Massaro spent 10 lonely and uneasy days holed up alone in his guesthouse in Thunder Bay this spring.

Mr. Massaro, a registered practical nurse who works in long-term care, was experiencing symptoms and quarantined himself away from the family home. After eating the dinners left outside his door by his wife, Mr. Massaro wished his daughters goodnight through their bedroom windows. His wife, Natalie Vibert, 34, was left alone to school the girls, 5 and 7, while working from home – this as she grieved her father’s recent death. In frequent video calls, she and her husband felt their panic mounting.

“It was really hard on us,” said Mr. Massaro, 36, who ended up testing negative. “There were a few times when Natalie had a rough go of it and I couldn’t do anything.”

Experts are just beginning to understand how working on the front lines of COVID-19 reverberates through the interpersonal lives of doctors, nurses and personal support workers. Many have brought fear, stress, guilt and helplessness home with them after long and traumatizing shifts, some shutting down emotionally with spouses. As the families of front-line workers find their footing, many are bracing for a resurgence of cases in the fall and growing anxious about how much upheaval their relationships can handle.

“If it’s a temporary situation, people are resilient. But what happens when we prolong this over a long time? There is despair, fatigue and stress at home,” said Sylvain Roy, a neuropsychologist and outgoing president of the Ontario Psychological Association. “Can we go through this for another four months? … There are limits to our flexibility and our resilience.”

For front-line workers privately struggling at home, new lifelines are emerging. The Canadian Association of Marriage and Family Therapists is offering three free sessions of couples or family therapy by phone or video call to people whose jobs put them at high risk of infection. Ontario front-line workers in any industry facing exposure can access six free, virtual, mental-health treatments with a psychologist, along with their spouses, children or other dependents, thanks to an initiative from the Ontario Psychological Association.

In Ottawa, psychiatrist Mamta Gautam has been hosting free peer-support sessions over the video-calling app Zoom for her colleagues in health care. And in British Columbia, researchers launched a new study that explores how high-risk health care work through the pandemic is affecting the quality of life of doctors, nurses, paramedics, respiratory therapists and their partners and spouses.

“We need good evidence about what this pandemic is doing to health care workers and their families to be able to support them,” said David Barbic, a clinical assistant professor in emergency medicine at the University of British Columbia who is leading the survey; 300 front-line workers have responded so far.

“They will need assistance over the next six months, the year and onwards,” said Dr. Barbic, who works as an emergency physician at St. Paul’s Hospital in Vancouver.

When the pandemic hit in the spring, Dr. Barbic was deeply concerned about keeping his wife and two children safe; the virus presented so many unknowns. Rapidly, the family’s daily routines changed. His wife, Skye Barbic, an occupational therapist and assistant professor at the University of British Columbia, struggled to find a moment of uninterrupted time to work from home while caring for their kids, 13 and 9. Their young son barely slept for two months, terrified his father would get sick at work. The boy would call at the start of his dad’s night shifts, seeking reassurance.

“I would say, ‘I’m safe, I promise. I’ll give you a hug and a kiss in the morning when I get home,‘” said Dr. Barbic, who showers at the hospital after his shifts and again when he gets home.

He and his wife are figuring out how best to cope, including “very honest communication.” Dr. Barbic talks often with his colleagues, sharing small moments of levity. He hikes the trails near his house. In the evenings, he and his wife limit how much news they consume, switching to Jeopardy! or Netflix when the headlines get too grim.

“We try our best,” Dr. Barbic said. “It has been challenging.”

Uncertainty, burnout and a complete upending of daily routines are serious issues facing front-line workers and their families, according to mental-health experts.

In her daily video calls with health care staff, Ottawa psychiatrist Dr. Gautam found people traumatized after witnessing outbreaks in long-term care homes and patients dying without family by their side. After their shifts, some agonized that they’d failed the sick; others were haunted by troubling images flitting across their minds.

“They found it hard to share these experiences with those at home,” Dr. Gautam said. “They did not want to burden them with it and felt they would not understand. At times, it led to them pulling away and withdrawing from loved ones.”

Hamilton psychotherapist Christina Walton has been counselling nurses and personal support staff who work in nursing homes hit by COVID-19. Some are bottling up their grief when they get home, zoning out on their iPads with video games or Netflix for hours – behaviour that hurts their spouses, said Ms. Walton, who specializes in couples and family counselling.

The challenge, she said, is to give front-line workers time to decompress both alone and with their partners. Ms. Walton urged families to get back to the basics: rest, hydrate, turn off the news and play Scrabble. “When you’re home, do what you can within those walls to connect and be a family,” she said.

In Thunder Bay, Mr. Massaro and Ms. Vibert are taking it one day at a time. Instead of fretting about a second wave, they are making the most of their time with their young daughters, hiking and biking in the wilderness and volunteering as lighthouse keepers on an island on Lake Superior.

When tensions occasionally flare between husband and wife, they try not to take it personally.

“Probably we have to be a little more forgiving,” Ms. Vibert said. “It’s not anything to do with our relationship. It’s the situation we’re in. You have to remember that this isn’t normal. It’s all new.”

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