Self-made billionaire and serial entrepreneur Elon Musk is best known for his pioneering work in the tech and science space. One of the main keys to his success is his emotional intelligence, as he displays with his family, employees and even upset Tesla customers.

But amid Tesla's launch of the Model 3 vehicle in July, the company's chief executive officer revealed he was going through a breakup. In an interview for Rolling Stone's latest cover story with reporter and bestselling author Neil Strauss, Musk admitted, "If I'm not in love, if I'm not with a long-term companion, I cannot be happy."

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Musk, 46, had been publicly dating Australian actress Amber Heard for about a year when the pair amicably broke up.

"It took every ounce of will to be able to do the Model 3 event and not look like the most depressed guy around," Musk said. "For most of that day, I was morbid. And then I had to psych myself up: drink a couple of Red Bulls, hang out with positive people and then, like, tell myself: 'I have all these people depending on me. All right, do it!'"

"I was really in love, and it hurt bad," Musk said, adding, "Well, she broke up with me more than I broke up with her, I think."

Leading up to the new Tesla launch, he said he had been in "severe emotional pain" for several weeks.

Strauss added that leading up to the event, Musk meditated "for pretty much the first time in his life to get centered."

Musk has been married twice before: first to writer Justine Musk for eight years, who is the mother of their five children, and later to actress Talulah Riley, which was on and off for roughly four years.

In 2012, between a divorce and his re-marriage to Riley, Musk told Bloomberg BusinessWeek about his balance between his work life and love life.

"I think the time allocated to the businesses and the kids is going fine," Musk told Bloomberg BusinessWeek reporter Ashlee Vance. "I would like to allocate more time to dating, though. I need to find a girlfriend. How much time does a woman want a week? Maybe 10 hours?"

Given that Musk splits his time between four companies, reportedly works between 80 to 90 hours a week, gets about six hours of sleep a night and even works while relaxing, Musk doesn't seem to get much time to himself.

When Musk and Heard ended their relationship last summer, Musk attributed the breakup to this very time constraint over social media.

"Long distance relationships when both partners have intense work obligations are always difficult, but who knows what the future holds," Musk commented on one of Heard's Instagram photos.

Musk told Strauss that from the time he was a child, he has never liked being alone. And he's onto something: The world's longest study on adult life and happiness has found that good relationships keep us happier and healthier for longer. Even business magnate Warren Buffett argues that "its much more fun achieving things in life with a partner."

There's even scientific research to back up Buffett's advice. A study published by Carnegie Mellon University found that people with supportive spouses are "more likely to give themselves the chance to succeed."

As for Musk's future companion?

"I'm looking for a long-term relationship. I'm not looking for a one-night stand. I'm looking for a serious companion or soulmate, that kind of thing," he said.

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