In 2015 Silicon Valley executive Dave Goldberg died suddenly while on vacation in Mexico with his wife, Sheryl Sandberg. Sandberg, the COO of Facebook, has spent the last two years struggling: to normalize life for her children, to get comfortable accepting the help of friends and family, to regain confidence at work, and to rediscover hope.

Adam Grant, the Wharton professor who is Sandberg's friend and writing partner, has been by her side, offering the comfort of research into resilience and tools for emerging from grief. The two have just published Option B: Facing Adversity, Building Resilience, and Finding Joy, a book that draws on Sandberg's journey, Grant's research, and interviews with survivors of the worst. (You can read our review here.) Grant recently spoke in an interview about how to come back stronger on the other side of suffering.

This is a book about people in pain. How did that affect your experience researching and writing it?

It was definitely a more emotional process than with my last two books. When writing Give and Take and Originals the predominant emotion for me was curiosity. Here the flood of emotions was very different. Sadness... but I also felt incredibly hopeful, especially as I heard the stories of people who have gone through some of the worst things you can imagine and come out on the other side stronger, with a renewed sense of meaning and purpose.

Isn't the way people experience grief very individual? Is there a universal path to recovery?

There was a psychologist, Gordon Allport, who said that every person is in some ways like all other people, in some ways like some other people, and in some ways like no other people. We wanted to capture a bit of each of those. Yes, everyone grieves in their own way and their own time. There is no question that it is profoundly personal. That does not mean there are not elements that are universal. The loss of control. The isolation. The intrusive thoughts. The loss of hope: being unable to imagine a future. And the loss of identity. If the person you lost was close to you, then that person is part of who you are. There is an element of, I don't know who I am without this person.

The book talks a lot about post-traumatic growth. What is that, and how does it change how we think about recovery?

I always thought when people went through hardships the best thing they could do was bounce back. It was pretty eye-opening for me to learn that alongside the negative emotions, growth can occur. When you look at people who have gone through a sudden loss, a life-threatening illness, an accident, a natural disaster, serious abuse--over half say there were some positive changes in their lives as a result. Not that they were happy those things happened. But a lot of people come out feeling stronger.

They also felt more grateful. It's ironic that when you go through a tragedy you appreciate more. You realize how fragile life is and that there are so many things to still be thankful for. That is a pretty common reaction. There is also evidence that when people go through tragedy together or if they have lived through similar kinds of tragedies it can bring them closer than they imagined possible.

The other kind of post-traumatic growth is about the future. When people go through tragedy they often become determined to make some good out of it. They want to do something worthwhile with the time that they have or to honor the legacy of the person they loved and lost. To do that frequently you need to be able to see new possibilities.

Sheryl Sandberg used a number of techniques to move herself toward post-traumatic growth. Which were the most effective?

A few days after Dave's funeral, Sheryl started to journal; and after four or five months she had written over 100,000 words. She was pouring her heart out. Oftentimes writing about traumatic events can improve our mental and physical health. It takes a tremendous amount of energy to bottle up intense emotions, and writing helps people express them and find coherence in what is happening to them. For Sheryl it was also good for her friends and family, who wanted to help but did not know what she was experiencing day-to-day. She realized, if I send my journal to people I can keep them all in the loop.

Other kinds of writing were useful too. She made gratitude lists. There is evidence that if you write down three things you are grateful for--even once a week--the happiness and health benefits are substantial. Also, she found that her confidence was shattered at work. She couldn't focus, felt like she couldn't put together a coherent sentence. I thought of some research I had done with a colleague where we asked people to write about their contributions. Sheryl took that as, I am going to write about three things I did well every day. The lists are hilarious. "Hooray, I drank fewer Diet Cokes!" But she was seeing that there were things she could still do, and that helped her regain confidence.

For months Sheryl was doing her best to hold it together as a parent and a leader. But she was not making time for anything that brought her joy. I remember on one of her Facebook posts she wrote that she would never feel pure joy again. I kept telling her it was not true. I told her about some evidence that if you write down three moments of joy every day it can elevate your mood. So she made a New Year's resolution in 2016 to do that. It proved to her that not every moment was equally awful. And it's changed her outlook. When something positive happened she would think, "Oh, this will make the notebook!"

When you have personally suffered adversity, have you been able to help yourself?

It is much easier to give advice than to do it yourself. The experience that stands out for me is five years ago--February 2012. Our closest family friend was killed in a car accident. It was shocking and devastating. It violated my belief that the world could be a just place. These endless loops would play in my head: imagining how the tiniest difference in decisions could have led him to not be on that icy road at that particular moment. The last time we had talked was a couple of months earlier, and I kept thinking, if I had stayed on the phone 10 more seconds, or if I had called him one minute earlier, then maybe his whole life would've been different. I realize that's a crazy, far-fetched version of the butterfly effect.

I was having a really hard time with that. Then my wife, Allison, whose background is in psychiatry, told me that it is really useful to imagine how things could be worse. At first I could not think of anything worse. He was in the middle of his life. He left behind a wife and three exceptional daughters. Friends and colleagues who adored him. Allison said he could've had that accident with people in the car. It completely shifted my perspective. I ended up sharing that insight with Sheryl--talking about how when Dave died of a cardiac arrhythmia that could have happened when he was driving their children. She had kind of the same reaction that I did. Oh my gosh! Suddenly I am flooded with gratitude that they are still here.

Did you see the recent story about Prince Harry finally seeking counseling for his grief over Princess Diana's death?

That was remarkable, especially his description of having wasted two decades before he finally decided he was ready to grapple with some of those emotions. What is powerful about someone like that opening up--and the same thing goes for Sheryl--is that it gives people permission to express vulnerability. Before, Sheryl would have told you she would not have been comfortable expressing those emotions at work or in a Facebook post. Now she realizes that when you have pain, expressing emotion is not a sign of weakness but of humanity. That was very clear in Prince Harry's revelations. I also think he gives permission for people to open up about the fact that nobody has perfect mental health all the time. That that should not be a source of stigma any more than if you cut your arm.

The book talks a lot about the social dimensions of grief. What advice would you give someone wanting to support or comfort a person who is suffering?

I'll tell you what I have always done wrong. My instinct is to offer reassurance to someone who is in severe pain. You have to be really careful about that. You can say, "You will feel better." And the person you're talking to can find counterexamples of people who say, "No, it has not gotten better." Don't say, "I know you'll be OK" to someone who is seriously ill. Really? How do you know I'll be OK? I might not.

It's better to acknowledge people's pain and let them know that it is OK to express it. You are there to listen. We are going to face this together. Also, avoid something I used to do all the time, which is to say, "If there is anything I can do, let me know." That is just a burden for the person who is suffering to make the request--even to figure out what they need. I love this article by [author] Bruce Feiler who says that instead of offer anything you should do something. Bring over a meal. Send a poem or a card. Just show up.

On the flip side, how would you advise a person in pain to manage social interactions? Suffering makes other people uncomfortable.

I remember Sheryl being stunned when a week or two after she lost her husband she would see people--people who knew Dave--and they did not say a word about it. The natural reaction was to feel that they didn't care. Eventually she learned that people did not want to remind her of it. Well, you can't remind her. She knows that Dave died. That is with her every second of every day. So I think the person in pain has to bring that out: that mentioning what happened is not going to trigger a flood of despair. Sheryl thought of a few ways to do that that I thought were really meaningful. One was just saying, "I am so glad to be with someone that I can actually talk to about this." That gave them an opening. She also learned that when somebody said, "How are you?" she needed to say, "Actually, I'm not OK. Here is what is going on." That is part of how you kick the elephant out of the room.

Mark Zuckerberg was very kind and supportive of Sheryl. But she is his right-hand woman and a good friend. As a leader, how do you push that kind of compassion down the chain?

About a decade ago I studied a Fortune 500 company that had set up an employee assistance program. It was funded through employee donations that were matched by the company. If an employee had any kind of severe event in their life--loss, an unexpected illness, not being able to afford your children's education--they had support available for you. We found people were more committed to the company after involvement with this program. It created a sense of pride and gratitude. I would like to see more organizations create these types of programs.

The other part of creating a compassionate organization is your policies. It is unacceptable that the average parent who loses a child in the United States gets three days off of work. We should do a lot more. Give people flexibility to come back in their own time. To work part-time. To think about how they want to manage the transition back.

How is Sheryl doing?

It's been really hard. It is one of the most heartbreaking things I've seen anyone go through. Her kids are growing up without a father. She loved Dave deeply.

But in tandem with that she is remarkably resilient. One thing I have learned from her is that often we become resilient for others. I don't think she would have recovered in the same way or found the same kind of strength if she were just doing it for herself. It was when we talked about how if she did not find a way to move forward it will be harder for her kids to do so that she really responded.

She doesn't get so stressed by the things that used to bother her. She expresses so much more gratitude. She has more clarity of purpose. And I think the Facebook mission has become more personal to her because she has seen how much being able to share helped her and helped other people. She is tremendously motivated that the horror of Dave's death does some good, and is more driven than ever to help people find strength. It is an honor to have a backstage seat for that.