Mark Zuckerberg didn’t bid adieu to Facebook (FB) cofounder Eduardo Saverin. Reggie Brown didn’t amicably part ways with the founding team at Snapchat. Those were serious divorces: messy, emotional, complicated, and painfully drawn-out breakups.

And there’s a reason for that. Building a company with another person is an intensely personal experience. The only metaphor that fits—the only possible life relationship that comes close—is marriage. It’s been nearly seven years since I met my cofounder. We’re still together and still building our dream, because—in many respects—we’re a darn solid couple.

For entrepreneurs looking to partner up for success, this may be obvious, but many of the very same factors that make for a long and happy marriage make for a long and happy cofounder relationship. Looking for a business partner? Be sure he or she is a soul mate.

See also: This Is Why Most Companies Go out of Business

Speak the same language
To make a marriage work, you need to see eye-to-eye on core issues like having kids, finances, and whose turn it is to take out the garbage. It’s no different in the business world. In fact, a full 65% of startups fail because of issues that arise among management teams, with most casualties stemming from “friendly fire.” You need to have similar values to not only get along, but to help make effective decisions in good times and bad.

The cofounders of Ben & Jerry’s, for instance, both wanted not only to sell ice cream, but to use their company to give back to the community. Family and business values brought together William Procter and James Gamble to form their household products empire.

In our case, a friend set me up with the amazing Mike O’Toole when I mentioned I was looking for a cofounder back in late 2009. After we met for burgers and beer in New York’s East Village, it was obvious that we shared similar views—not just about building a startup, but about values like honesty, integrity, and transparency. Over the years, that has helped us get through some pretty tough stuff: a major pivot, loss of one of our fellow cofounders, recruiting horror stories, navigating the intricacies of fundraising—you name it. If we didn’t speak the same language, we’d be lost.

Opposites attract—and perform
Having said that, when finding a life partner, you don’t want a clone of yourself. You need someone who fills in your blind spots and challenges your ideas. This is even more important in business. At Apple, for instance, Steve Wozniak was focused on the technical side, while Steve Jobs was obsessed with design. That productive tension gave rise to a truly game-changing machine.

I had a feeling Mike and I would be a fit for some of the same reasons. Our idea was to completely transform the way that apartments get leased and marketed. We envisioned Nestio as an online platform where landlords and brokers could access info and tools in real time. From the beginning, Mike’s domain has been product development and engineering, while I’m focused on sales and business development. We’re kind of like two entrepreneurial warriors, standing back to back, defending each other against everything that could kill a startup—competitors, product hiccups, funding shortfalls, etc.

While it was no surprise, I’ve since read some interesting statistics that “balanced teams with one technical founder and one business founder raise 30% more money, have 2.9 times more user growth, and are 19% less likely to scale prematurely.”

Trust trumps all
Lack of trust can absolutely destroy a marriage. Nagging doubts about loyalties and motives turn relationships toxic. And when things get rough—and they always do—that cracked foundation won’t hold.

Gauging trust with a cofounder isn’t an exact science. Partly, it’s gut: a sense that the other person is giving you the full picture. But more importantly, it’s habit: seeing him or her come through for you time and time again. I knew right away that Mike was the right business fit, but our commitment deepened when everything seemed like it was falling apart and we had to pivot the company.

I still remember the time I was tucked away in a conference room—long after most everyone else had gone home—head in hands, overcome with stress. Mike opened the door a crack, peaked in, and sat down. In the midst of all of the chaos, he helped me talk things out. He closed with three words that I’ll never forget: “I’ve got you.” We got through that rough patch (and now are poised to double our staff size), and I couldn’t imagine making it out to the other side without trust. If that’s not soul mate-type stuff, I’m not sure what is.

Caren Maio is founder and CEO of Nestio, a residential leasing and marketing platform.