She is the nurse in the surveillance video who barely steps outside the hospital door to look for my wife, and then doesn’t see Laura slumped on a bench about 70 feet away in the predawn darkness, suffering a deadly asthma attack.

“Nurse X,’’ I called her, and while she was just one of many people whose actions or inactions led to my wife’s needless death outside CHA Somerville Hospital, she was the only one who might have found Laura in time to save her. After months of investigating what happened that morning two years ago, I needed to know: Was Nurse X sorry?

I now have an answer.

“Her heart is broken,’’ the hospital’s chief of nursing told me. However, Nurse X doesn’t feel she did anything wrong, saying she didn’t know when she stepped outside that Laura was near death. She feels that I unfairly targeted her in the story I wrote last month for the Globe Magazine, “Losing Laura,’’ about the ways our 911 and emergency health care systems failed my 34-year-old wife.

Hospital officials’ openness in sharing Nurse X’s feelings — which, while difficult to hear, are in ways understandable — is part of an extraordinary turnaround. Since the publication of Laura’s story, the leaders of Cambridge Health Alliance, Somerville’s parent, have gone from a cold, corporate “no comment’’ to being honest and accountable, literally embracing me and apologizing for their role in Laura’s death. When I ask for documents, they provide them. When I tell them there are still things I don’t understand, they meet with me, my digital recorder on the table, everything on the record.

Now, the organization’s board of trustees has hired the law firm Foley Hoag LLP to review every aspect of Laura’s case, posing nearly 30 questions, such as “Why didn’t CHA apologize to Laura Levis’s family in 2016?’’ and “Does the board have trust in executive leadership?’’ Former attorney general and Foley Hoag partner Martha Coakley is expected to help lead the investigation.

“I know people may not believe that we’re really changing, but we’re really going to try,’’ Josh Posner, trustee chairman, told me before the board meeting this month, at which I spoke. “I’m glad you’re here.’’

In medicine there is something known as “the apology and disclosure’’ movement. It’s when health care organizations address their mistakes and failings head-on with patients or victims’ families in the hopes that by doing so, there will be less animosity, greater understanding, and potentially less litigation. Cambridge Health Alliance is finally joining this movement, albeit only after the public outcry that Laura’s story has engendered.

They began their new path on Nov. 13, the day CEO Patrick Wardell and his top managers finally met me in person at the Globe offices. I wasn’t sure whether I would shake Wardell’s hand when I walked in the room; he looked at me, unsure whether to offer it.

But we did shake — the most difficult handshake of my life. And, maybe, one of the most important.

I was not going to sue the hospital, though I held them responsible for Laura’s death. State law limits malpractice damage awards to $100,000 against public hospitals, which might not be enough even to cover legal costs. It wasn’t money I wanted from the hospital, anyway.

“Just be human beings to me,’’ I said to them. “You have the opportunity to stop hiding and start being part of the solution, to share what happened to Laura to save someone else’s life. It’s your choice.’’

Wardell and his staff bowed their heads. They looked at Laura’s beautiful photo, propped up next to me on the table. I think they struggled not to cry.

From that point on, Somerville Hospital’s leaders have expressed their true emotions to me — shame, sadness, and remorse for what never should have happened.

Laura’s death was anything but simple, the result of communication errors, improper emergency room signage, inadequate security plans, and safety nets that snapped way too easily. Cambridge Health Alliance has far to go to correct all these problems, and their leaders now acknowledge that.

“We have great sincerity in wanting to make amends because it strengthens us, it strengthens our ability to care for the next patient who comes in,’’ Wardell has told me.

Based on federal, state, and local investigations into Laura’s death, I was able to reconstruct every minute of that September 2016 morning. But as the hospital had declined all comment, I was left wondering many things, including why Nurse X made such a limited search for Laura when she stepped outside.

Feeling the onset of an asthma attack, Laura had walked to the hospital from a nearby apartment just after 4 a.m., but she immediately ran into problems getting inside. Two sets of doors, 100 feet apart, led to the emergency room. Neither had an emergency-room sign above it, so she chose the entrance that was more brightly lighted, but it was locked. She called 911 to ask for help before collapsing on a waiting bench, just 29 feet from the second door, which was open.

Police called the hospital and told Nurse X that a woman was having an asthma attack outside, and she walked out of the ER to look for her. But Nurse X stepped only an arm’s length outside the hospital before returning inside. She didn’t see Laura because it was too dark, Nurse X told investigators.

Hospital leaders, at my request, interviewed both Nurse X and a hospital security guard on duty in the ER that morning, who said he would have searched for Laura had Nurse X asked for his help. They insist they did not know the seriousness of the situation, and what I’ve learned since supports that. Though Laura told the 911 operator that she felt like she was “dying,’’ police did not pass that along to the hospital, they said, and they never spoke directly with Laura, so they never heard the terror in her voice that was so apparent in the 911 recording. As a result, Nurse X had no way of knowing how much danger Laura was in. (State 911 leaders and Somerville’s police and fire chiefs met with me last week as well, promising that Laura’s call will bring about changes in training.)

“Laura’s call is so strikingly different than what we heard’’ from police, said Dr. Assaad Sayah, CHA’s chief medical officer. “I don’t think the nurse in her mind was expecting to look and find someone who was critical. . . . Otherwise, she wouldn’t have gone by herself.’’

Lynette Alberti, CHA’s chief nursing officer, said Nurse X was just being practical when she went back inside rather than continuing to search for Laura.

“She thought rather than trying to scour the whole area, because it was dark and she didn’t see anything, she should find out exactly where she is,’’ Alberti said. “That’s why she called the police to get a phone number [for Laura] because she thought she’d call her and tell her where to go.’’

Alberti and Sayah were adamant that Nurse X “never stopped looking’’ for Laura, obtaining her cellphone number and then calling her. Nurse X and a nursing assistant were just about to tell the security guard that Laura was outside and he should go look for her, Alberti said, when a Somerville police officer came running in, alerting the nursing assistant that Laura had been found by firefighters.

“It seemed to all be happening simultaneously,’’ Alberti said.

Two years later, “there’s not a day that goes by that she doesn’t think about it. She knows that she can’t feel your pain, but the whole department is devastated by it,’’ said Alberti.

But she doesn’t second-guess her actions that morning.

“I don’t really believe that the nurse necessarily feels that she failed,’’ said Alberti. “This is a dedicated seasoned nurse that’s worked for us for a very long time, and is devastated that her judgment’s in question, and that the ER as a team is in question, [since they] really tried at the time to do the right thing. I think she feels a bit targeted.’’

It did all happen fast — the Somerville officer came running in just eight minutes after Nurse X first learned Laura was outside the ER.

But for someone struggling to breathe, every minute is vital — and panic, which is surely what Laura felt after finding an ER door locked, only accelerates an asthma attack. More than 3,500 people die annually from asthma in the United States, according to the Centers for Disease Control and Prevention. A veteran registered nurse would have known the risks. Federal law, as well, required the entire hospital grounds to be searched for a patient in distress.

“Should the nurse have walked from one door to the other door? Should the public safety [officer] have gone out and searched? You know the answers to all these things,’’ Sayah said. “What we can share is what happened and what people were thinking . . . and unfortunately, the outcome was terrible.’’

Denial helped me survive for a long time after Laura was gone — and deal with my feelings of guilt and pain that, because we were temporarily separated while we worked out an issue in our marriage, I wasn’t there to help her that morning. Maybe, Nurse X, in her own way, feels something like that, too. I imagine it would be so hard for her to continue doing her job if she truly believed her failure to look harder for Laura in those critical minutes cost her life. Maybe she feels that because of all the other mistakes that came before hers, from 911-operator errors to the hospital’s lack of emergency-room signs, there was no way she could have saved her. Maybe one day, she’ll tell me that herself.

I, of course, will never accept the decisions Nurse X made that morning — what husband could? — but I am long past the point of wanting her to suffer for them. It’s why I chose not to reveal her name even though I had fought for months to obtain it. It’s why I choose again not to reveal it now. I want to honor Laura by seeking change, not vengeance; maybe one day, Nurse X will see that, too.

That the hospital is now being honest with me comes with a cost. They’ve answered so many questions for me, but what the answers add up to is that absolutely nothing went right for Laura that morning.

For instance, I now know that there was a surveillance monitor in the emergency room that morning that showed Laura outside the ER door. Apparently, no one was watching it.

The surveillance video showing Laura’s collapse likewise could have been viewed inside the hospital’s security office. But the only two guards on duty were watching three behavioral-issue patients who had been in the ER since before 11 p.m. No one else was watching the security desk all night; management saw no need to call in a backup.

The circumstances of Laura’s death, I’ve also now learned, were possibly downplayed by those whose job it was to report it up the ranks.

The hospital’s initial report to the Department of Public Health regarding Laura’s death inaccurately claimed that both a nurse and a security guard searched the property for Laura. It also claimed that lighting and entrance signage was appropriate, that Laura was found near the ambulance bay instead of steps from the main door of the hospital, and that I had been notified about what had happened that morning.

Wardell told me it was never CHA’s intention to have hidden the truth from me or Laura’s family. No one who treated Laura in the ICU of CHA Cambridge Hospital, where she was transferred after her heart was restarted, knew what had happened. In fact, Wardell and hospital leaders say they only learned the full story of what happened when DPH investigated nearly two months later.

“In a more typical patient injury situation the expectation is that it’s full disclosure,’’ he said, adding that he was not trying to help the hospital elude a potential lawsuit. “It was a dramatic failure there.’’

That Cambridge Health Alliance is taking Laura’s death so seriously does give me hope. They’re making significant strides in correcting many of the problems that contributed to her not being found, from a major overhaul of their entire security network (planned well before Laura’s death, but, unfortunately, not completed in time to help her), to hiring an outside consulting firm to review signage and patient access, to planning safety drills for staff at all three of their hospitals on how to respond to a patient who’s either lost outside the hospital, or can’t get in.

Laura’s death was completely senseless. Using it to save other lives is the only thing that makes sense to me, as I continue to struggle with her loss.

“Peter,’’ Wardell said, as we reached the end of our last talk, “The payback for us at the end is if we can really make a difference here and other places.’’

“That’s my goal, too,’’ I said.

We shook hands again, which still wasn’t easy

But, it wasn’t quite as hard.

Peter DeMarco can be reached at peterdemarco @hotmail.com.