Lyft Co-Founder John Zimmer Reveals 'Overwhelming' Stress Led to 'Cycling of Bad Thoughts' and Depression

courtesy Lyft John Zimmer

Lyft president John Zimmer knows what it's like to lose sleep as you stay up at night, worrying over problems that haunt your days.

That's because it was his draining existence for an extended period of time, the Lyft co-founder, 38, tells PEOPLE.

About seven to eight years ago, Zimmer was living on "very little sleep, very poor-quality sleep," he recalls. "I could not slow the negative thoughts down."

Back then, the Connecticut native was involved in a high-stakes rivalry between Lyft and its biggest ridesharing competitor.

"Uber raises [more than] $3 billion from the Saudi government. We recently go from minors to majors," Zimmer says of the two brands' early days.

Matters were complicated because his fellow Silicon Valley business had a "very different set of values," he claims. (There have been a series of legal disputes involving the competitors over the years. In 2017, for example, a group of Lyft drivers filed a class action lawsuit against Uber for allegedly using the software known as "Hell" to track their drivers, according to the Los Angeles Times. Ultimately, the case was dismissed in September 2018. PEOPLE reached out to Uber for comment.)

To add to his woes, Lyft was dangerously close to collapse at one point, Zimmer says: "We're literally facing five months. If we spend the same amount we're spending at that point, five months in a row, the bank account will say zero."

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"It was extremely overwhelming," adds Zimmer, who co-founded Lyft with his friend, the company's CEO, Logan Green and is currently healthy. "We're a mission-orientated business, and because I love pouring myself into work with a purpose, I had tied my own wellbeing and identity to that."

It reached the point where Zimmer had trouble gaining "perspective outside of myself, separate from Lyft," he explains. "So when the company moved towards a crisis in that time period, it became internal. There were clearly moments where I didn't think the business would survive, and that was so internally existential for me."

courtesy Lyft John Zimmer (right) with Logan Green, Lyft's CEO, with whom Zimmer co-founded the company

Gradually, the extrovert found himself trying to motivate his team while battling a depression he couldn't accept.

"I think I kept that mentality of, 'I'm so fortunate. I have nothing to complain about…'" Zimmer says. "That played in my head a lot and, therefore, it suppressed some of the processing of my emotions."

Meanwhile, behind closed doors, those closest to him could see he was struggling.

"I locked up all these emotions and it created this very dark and heavy cloud around how I felt when I wasn't on stage, whether that was in front of the team at the office or talking to media," he says.

His wife Cristina had a close-up look at the toll it was all taking at all hours.

"It could manifest in having trouble getting out of bed in the morning," he says. "It manifested in me burying myself in solving the work so that I could unblock the depression."

But ignoring his emotions — the stress, anxiety and sadness — wasn't helping. It was only making the situation worse.

"You get stuck in this dark cloud, and this exhaustion and this cycling of bad thoughts: 'Will this survive? Am I not good enough?'" he says. "[They] are compounded by the lack of sleep. Then you can't get to sleep, and things just start getting worse and worse."

Fortunately, Cristina and a close friend — who sent him links to five local therapists — convinced Zimmer to get help. His first therapist reframed how he saw depression and "destigmatized" it, as Zimmer explains, pointing out that — just like a physical condition — if you're mentally unwell, you seek a doctor's help.

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Somehow that clicked, and through a "combination of therapy, medicine for a period of time," talking to friends and exercise, Zimmer found the tools to help him find balance and recover.

"Very physical exercise is the most helpful thing by far," says the father of two, who works out three days a week. "I started boxing and CrossFit, just doing something so physical to a point where I couldn't be rotating on those thoughts."

"If I was doing boxing training, I had to be extremely present or else I was going to get punched in the face…" he adds. "That really extreme physical exhaustion pulls me out of those bad thoughts."

courtesy Lyft Lyft co-founders (L-R) Logan Green and John Zimmer, who offer their employees mental health resources.

Zimmer's experience with depression has informed Lyft's mental health policy. It's something he feels strongly about. Employees, for example, can get up to 12 therapy sessions at no cost. They also have access to guided meditations and cognitive behavioral training workshops. So far, 30 percent of their team members actively use those services.

Zimmer hopes that speaking out and sharing his story will help destigmatize depression and encourage others to seek support.

"No one is immune to mental health challenges," says the exec, whose company clearly survived the crisis that gave him sleepless nights. "For the public conversation to expand and increasingly lessen the stigma, it's important to be open and vulnerable."

He adds: "It can happen to anyone, and I would say it probably does happen to most everyone at some point in their lives."