In the early years of Stonyfield Yogurt, my husband, Gary, and I acted like the three wise monkeys. When it came to the company's finances, I covered my eyes and ears so as to see and hear no evil. Gary went along by covering his mouth.

I embraced ignorance (or innocence, as I prefer to call it) for emotional survival. The company was hovering near bankruptcy, and I couldn't bear to learn the gory details portending its demise. I knew I should know what was going on. Our entire future was on the line. But I wanted to listen to a financial report the way I watch the movie The Shining: running out of the room during particularly terrifying scenes.

I wish I could have been the supportive spouse who listens sympathetically, then calmly puts everything into perspective. As it was, Gary accepted our don't-ask-don't-tell pact because it prevented my fear from making him crazy. He avoided what he calls the double penalty—intense stress at work compounded by intense stress at home. After a day spent putting out fires, he didn't need my alarm ringing in his ears.

Launching a company is a risk couples assume together. But unless they are equal business partners, only the entrepreneur has firsthand knowledge of every hurricane and hiccup. The CEO comes home to a spouse whose interest is mixed with anxiety. Sometimes, beneath the query "How was your day?" lurks the plea "Reassure me, or at least don't say something that will leave me cowering in the coat closet clutching a vodka tonic."

Most couples don't know right away how much about the business it's optimal to share. Spouses may start out as enthralled spectators, closely following every play and—even when the home team is hopelessly behind—cheering from the stands. Some continue that way. But others discover they have low tolerance for trouble and would just as soon remain in the dark. Entrepreneurs, meanwhile, adopt reticence out of self-preservation. As one CEO put it, "Entrepreneurs have people freaking out on them all day long. We don't want the same thing at home."

The ensuing silence stifles conflict and drama. But it also forces the entrepreneur to shoulder the burden alone. That can send him into what one spouse I talked to called battle mode: quiet, tense, and toxic. The spouse, meanwhile, worries about the entrepreneur and also worries about whatever unknown catastrophe the entrepreneur is worried about. Couples become disconnected from huge chunks of each other's emotional lives. Communication frays and with it, empathy. "Ultimately, I was willing to sacrifice some intimacy to avoid conflict," Gary told me.

A business can be an endlessly fascinating subject that encourages the exchange of ideas and eager speculation about the future. Or it can be a marriage's third rail, which a couple dares not touch for fear of shock waves.

One way to defang bad news is to limit when it's shared.

Risk is easier to live with when you have some degree of control. Entrepreneurs are hands-on with their companies; confidence in themselves translates into confidence that they can weather any storm. And because they see the big picture, they have perspective. They can distinguish between things that kill and things that make them stronger.

Spouses, by contrast, have little power beyond the right to advise and—occasionally—consent in business decisions. Their impotence increases their fear. Lacking the thorough context and nuanced understanding that come from working in the business, they may magnify problems or focus on the empty half of the glass. "I worry," one spouse told me, "but I don't say anything. The problem festers, and then I get angry, because I don't have any money or solutions to fix things, and it's not my responsibility to solve it." Entrepreneurs, in turn, keep quiet to save their spouses' agonizing about matters beyond their control.

Richard Haig once shared everything with his wife, Pam. Then he started Haig Service Corporation, an alarm company in Green Brook, New Jersey. Richard recalls the evening he told Pam that the company faced higher estimated taxes because it had had a good year. The "good year" part barely registered with his wife. But she lost sleep over the tax bill. "I considered it just another day at the office," Richard told me. "I was dumping 10 times the weight on my wife's shoulders that I felt on mine." Now he avoids discussing the company at home. "Her reaction made me realize that the hurdles I jump every day at work are, to nonentrepreneurs, the equivalent of jumping out of a plane without a parachute," Richard said.

Even spouses who work together need not be equally informed. Keeping information from a partner may sound patronizing. But if that partner deals poorly with adversity, there are good reasons to do so. Employees and customers take their cues from the owners. I spoke with one CEO whose husband manages sales at her company. "I feel like I can handle our precarious financial state better than he can," she told me. "If he knew how close to the line we're cutting it, I'm afraid he would spiral into a negative place, where he'd feel all this wasn't worth it. My fear is that he'd walk into every sales meeting with customers with his head hung low. Frankly, I think he's grateful to me for taking on the burden of the worry."

I admire couples that talk with absolute candor about the company, and whose relationships benefit from the common interest. Paul Williams, president of Isite Design, a digital consultancy in Portland, Oregon, tells his wife, Leah, everything. "When it comes to business, ice runs through her veins," said Paul. "She doesn't get stressed. Without our collaboration, I'd be missing a confidante and valued partner." Still, I couldn't help wondering whether Isite's track record-one unprofitable year out of 14-made that openness easier. Leah acknowledged that an unstable business would have made information sharing more challenging. "I would have just wanted him to fix it," she told me.

So, knowledge is scary. But, outside the Garden of Eden, ignorance isn't bliss, either. What couples need are strategies to calmly and productively discuss their companies' fortunes.

One way to defang bad news is to limit when it's shared. That at least stops unpleasant subjects from tainting every part of the day. Mitchel Harad of San Francisco owns a business consultancy. His wife, Kristin, has a financial-planning firm. The couple sets aside 30 minutes every week for a formal business meeting to discuss both companies and the family's finances. All that needs saying gets said in that half-hour, so worries don't rear up unexpectedly as husband and wife are brushing their teeth before bed. "At that hour, even innocuous issues blow up," said Mitchel.

Bad news is also less chilling when families hedge their bets. Dan and Allison Turner can discuss any development with equanimity because they have a Plan B if something goes wrong at TCG, Dan's IT government contracting firm in Washington, D.C. "I don't know how entrepreneurs function without a personal safety net," said Dan. "We've laid out things we can do—like sell our house and buy a less expensive one—if cash gets tight." During one tough period, Dan didn't take a paycheck for three years. "I remember worrying but not second-guessing," said Allison. "Our backup plan made any worst-case scenario less scary."

As for me, I was most comfortable hearing about Stonyfield during board meetings. There I received a detailed snapshot of the company, stripped of emotion. And it was reassuring to watch Gary address problems coolly and professionally while his audience reacted as though everything were normal.

As my husband embarks on new, uncertain ventures, he knows from experience that there are good times and bad times to talk to me about his businesses. "The good times are when you're relaxed and feeling upbeat, or when you're in the company of others who react calmly," he told me. And the bad times? All the rest, Gary said.