NEW YORK (AP) — The path that took Deven Black to his bloody death in a gritty homeless shelter was as baffling as it was tragic.
This was a suburban dad, a nationally recognized school librarian. In just three years, he had become destitute. He had derailed his career with an inappropriate encounter with a female student, had blown up his marriage by giving thousands of dollars to paramours online and had gotten involved in a bank fraud scheme for their sake.
Doctors diagnosed depression. Relatives and friends tried to help, confronting and struggling to get through to him.
A year after his death at 62, renowned brain experts have confirmed that more than depression was at work. They recently presented his case as "the mayhem of a misdiagnosis " of a rare disorder. His estranged wife had suspected it, but his doctors hadn't pushed to test him, and at least one had concluded he didn't have it.
"I'm just so angry that this happened to him," says his sister, Loren Black. "And I really wish that we could have figured out how to protect him."
Black's career hit a high point at a black-tie gathering in the fall of 2013, when got a national award for school librarian of the year .
A smart but contrarian high-school dropout, he'd been a radio reporter on Cape Cod, a bartender and the manager of a popular British-themed pub in Manhattan for nearly two decades. After going back to college, he became a New York City public school special-ed teacher in his 50s, then turned around an outdated middle school library.
He and Jill Rovitsky Black, who'd met on a blind date, marked their 30th anniversary in 2013. They had a son in college, and a home in Nyack, a historic, artsy town on the Hudson River.
But the seeds of Black's decline were germinating.
School investigators had recommended disciplining him after a student said he'd told her she looked sexy and sometimes put his arm around her shoulder, records show. He gave investigators a different account but was suspended without pay for two months in 2014 and removed from his librarian job to substitute teaching.
Feeling down as the investigation played out, he turned to online relationships while withdrawing from real-world ones, according to friends, relatives and court records.
And his wife started finding receipts showing he'd sent thousands of dollars to people mostly in Ghana and Nigeria.
He said it was an investment. She warned him he was being scammed. Friends urged him to cut off his online contacts. But he plunged deeper into a web of virtual romances. He was so broke by the fall of 2014 that his wife paid his first month's rent and security deposit when he moved out.
A few months later, Black was under arrest in a Bronx jail. At the behest of an online "girlfriend" he said invited him to start a cocoa business, he had deposited a series of fraudulent checks, withdrawn more than $146,000 in cash and given most of it to her, court papers say.
What was Black's problem? His wife kept thinking about an unusual disorder she'd heard about through her job at a medical-education company.
Frontotemporal dementia often emerges in patients' 50s or 60s and can scramble their personality and behavior while leaving memory intact, at least for a time. "Behavioral variant" FTD patients can become uncharacteristically impulsive, behave inappropriately and make bad financial decisions. And some patients' families carry a genetic mutation linked to both FTD and amyotrophic lateral sclerosis, also known as Lou Gehrig's disease. Black's late mother and brother both had it.
"Enough of the descriptions of the condition ring true that I think it's worth consideration," his wife wrote in a 2015 email to a therapist who saw him in connection with the fraud case, as did a forensic psychologist.
The psychologist concluded in court papers that Black didn't meet the criteria for an FTD diagnosis at the time but recommended continued monitoring.
Black had been diagnosed with depression while hospitalized as a psychiatric patient for a week in June 2015, according to court records. He'd become suicidally despondent after one of his supposed online sweethearts didn't show up from Ghana for a promised visit, his sister says.
By the time Black went to his October 2015 sentencing, he'd been evicted and was living in a homeless shelter. Friends and relatives say they feared he'd bring his schemes into their homes if taken in.
Reassigned from teaching to administrative work after his arrest, he was facing at least suspension after pleading guilty to conspiracy to commit bank fraud. But he told the court in a letter he was "on my way back" to stability.
He would never get there. On Jan. 27, 2016, police said, Black's throat was cut by Anthony White, his volatile, 21-year-old roommate in an East Harlem shelter for men with mental health problems. White's family said he wasn't a killer, but he never answered the allegations himself. He fled, disappearing until his decomposed body was found in the Hudson two months later.
The day after Black's death, his wife called Dr. Brad Dickerson, a professional acquaintance who runs Massachusetts General Hospital's FTD Unit. He quickly agreed to explore Black's case.
With Black's story and his family's history of ALS, "you've almost got two smoking guns," said Dickerson, who worked on the case with Columbia University neuropathologist Dr. Jean Paul Vonsattel.
Confirmation came in an image of chemically stained, microscopic brown specks that marked deposits of a protein linked to FTD and ALS on a bit of Black's brain.
FTD affects an estimated 50,000 to 100,000 or so people nationwide. It can be diagnosed in living patients by psychological tests and brain scans, but symptoms are frequently misattributed to depression, bipolar disorder or just a midlife crisis, experts say.
Black left behind a strangely apt memento of a life that unraveled, and of his loved ones' quest to understand how this could happen.
"If you expect simple answers to complicated questions," his Twitter profile says, "you're in the wrong place."
The Association for Frontotemporal Degeneration