Then suddenly, he was being airlifted to a hospital where he'd undergo emergency brain surgery to remove the tumor that had been causing confusion and a massive headache for weeks.
The 39-year-old dad, who is the service director for Mercedes-Benz of New Rochelle, has been diagnosed with a rare and aggressive form of brain cancer that has turned his life upside-down.
Much of the future is unknown for Nelson and his family, which is why his wife, Jenny Bertolini, says these days, they're focused on the here and now.
"We don't know what tomorrow brings," said Bertolini, trying her best not to become emotional on a phone call with Daily Voice. "We're sharing our story to show that this came out of the blue for us, and we want to show others the importance of cherishing every moment."
More than $72,000 had been raised on a GoFundMe for Nelson's family as of Saturday, Nov. 26. Nelson is his family's primary source of income, has been out of work since early September.
Bertolini was the first to notice a shift in her husband's behavior over the summer, she said. He seemed to be very forgetful and had an unusually slow response time during conversation.
Bertolini really started to worry when Nelson began confusing their sons, 2-year-old RJ and 9-month-old Evan. An appointment with a neurologist was what Nelson needed, Bertolini knew, but all the doctors were booked up until November.
Waiting for a doctor simply wasn't in the cards for Nelson, whose health continued to decline, rapidly.
On Labor Day weekend, Nelson complained of a pounding and relentless headache. He slept for one day, and then another, and then another.
Bertolini practically begged her husband to seek treatment. And so, he went to an urgent care clinic, only to return home after apparently being told by medical professionals to stay out of the sun.
Nelson's wife knew better than to accept that for an answer, and told her husband to get to a hospital, and it's a good thing he did.
In excruciating pain, Nelson, who resides in the borough of Norwood in Bergen County, New Jersey, drove himself to Pascack Valley Hospital while a worried Bertolini looked after the boys.
"The hospital staff said 'Why are you here?' and Richie said, 'I don't remember, all I know is my brain hurts,'" his wife recalled.
A CAT scan found a large mass on Nelson's brain, with swelling so severe that Nelson was quickly losing awareness, his wife said.
Hospital workers called Bertolini and insisted she come down. When she showed up, they explained that Nelson would need to be airlifted to Hackensack University Medical Center for emergency treatment.
Nelson was put on steroids to reduce the swelling and, days later, underwent emergency brain surgery to have as much of the mass removed as possible.
A biopsy confirmed the mass was a cancerous tumor: Primary central nervous system lymphoma, an aggressive form of cancer that was seriously impacting Nelson's speech and motor skills.
To put it simply, Bertolini says, "It's just basically taking over life — throwing a curve ball, turning it upside-down for the worst."
It hasn't been easy.
Nelson switched over to Memorial Sloane Kettering Center, where he's admitted for a week every other week, as he undergoes chemotherapy. He has to complete a total of eight rounds. After that, they'll look into a stem cell transplant.
"If all of this works, it will help him stay in remission," Bertolini said. "This tumor isn't gone and it's still affecting him. If we stop treating it, it will kill him. We're trying to fight this."
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