Don't miss Sheryl Sandberg's hard-earned wisdom on leaning in with 'Option B'

Denial, anger, bargaining, depression, acceptance. Now what?

Sheryl Sandberg has given us a name for the part of life that comes after we've cycled through the classic five stages of grief and into the days and months and years that stretch ahead uncertainly.

Option B.

It's the stage in which you redefine and reclaim your life after the one you thought you'd have is cruelly interrupted.

Sandberg is 45, with two small children. She's the chief operating officer for Facebook and the author of "Lean In: Women, Work and the Will to Lead."

She was celebrated, she was envied, she was a best-selling author and one of the biggest names in international business.

On May 1, her husband, Dave Goldberg, CEO of SurveyMonkey, died in a treadmill accident during a family vacation. He was 47.

"I have lived 30 years in these 30 days," she wrote. "I am 30 years sadder. I feel like I am 30 years wiser."

That wisdom encompasses everything from life is ephemeral to move over for ambulances, people.

It includes guidance for those who are grieving, and those around them - including what to say, what not to say, and the importance of saying something.

Returning to work after her loss, Sandberg explicitly invited colleagues to ask questions that might upset her. She did not promise not to get upset. "Speaking openly replaced the fear of doing and saying the wrong thing," she writes.

Go ahead and overshare, in other words. And hit the "like" button if you get the chance. They'll know what you mean. (By midday Thursday - a little over a day after Sandberg bared her soul on Facebook - more than 700,000 people had done just that.)

She admonishes a friend who says he hates birthdays. "Celebrate your birthday, goddammit. You are lucky to have each one."

In a single anecdote that swings from anguish to gratitude to bewilderment to resolve, she describes an exchange with a friend who volunteered to stand in for her late husband in a father-child activity.

"I cried to him, 'But I want Dave. I want Option A,' " she writes. His response: "Option A is not available. So let's just kick the (expletive) out of Option B."

The essay ends with a pledge to her late husband to work at that from now on.