Meanwhile, Singh's brother Gurjot Singh said the couple had "a really nice relationship."
In the texts, copies of which were obtained by the Daily News, Singh, 25, demands money from Nadia's friend Thomas Singh (no relation), saying that he'll let Thomas talk with her if he'll agree to wire him $100.
When Thomas refuses, Bhupinder gets agitated.
"Okay think whatever bye I promise u this now u wont hear her ill f---in make sure bye u lost the chance," one reads.
"Look for us in the whole United States I guarantee my life u wont find us," threatens another.
The texts kept coming, right up until Feb. 12, when police in Solon, Ohio, arrested Singh at his parents' house at the request of Marple Township Police detectives. When cops arrived, Singh tried to give them the slip through the apartment's rear door, according to police documents. One of the couple's two children, a 1-year-old girl, was with Singh's parents in the apartment, authorities said; their other child, a 5-year-old boy, lives with Malik's parents, according to Khaled.
When he was brought into custody, Singh had Nadia Malik's cellphone (which Marple cops used to locate him) and driver's license, as well as a Greyhound bus ticket dated Feb. 9 that showed he had traveled to New York City from Philadelphia before boarding another bus to Cleveland by way of Washington, D.C., according to Marple Township Police Chief Tom Murray.
Singh told Solon police that he had left Nadia, 22, in Philly after they had a "verbal argument concerning their relationship," according to police documents. He also admitted sending the texts demanding money in exchange for letting her friends and family talk with her.
He's now back in Delaware County, in custody at the George W. Hill Correctional Facility in Thornton awaiting a hearing for parole violations after his trip to Ohio, according to court records. He hasn't been charged in Nadia's death, according to Marple Police Detective Barry Williams.
That's not enough for her brother.
"She was a good kid until she met this guy," Khaled Malik said. "There was nothing out of the ordinary in her life until she met him."
Malik described his sister as studious, quiet and shy. She was a dedicated worker, and took a job at an Upper Darby CVS while pursuing a pharmacy degree at the University of the Sciences.
But Singh was possessive of Nadia during the five years they were together, her brother said, and his family rarely saw her. She lost her job at CVS after missing too many of her shifts, "which is nothing like her," he said.
The last time he heard from her was in mid-January, he said, when she told him that she wanted to leave Singh for good.
"It was an up-and-down relationship," Malik said. "I think after she finally tried to leave him, he finally freaked out, and didn't know what to do."
The last time anyone saw Nadia Malik alive was Feb. 9, according to Williams. She was seen behind the wheel of a black Nissan Altima, on Market Street near Millbourne Avenue in Upper Darby, Williams said.
When friends and family tried to locate her, the texts started, and a concerned Thomas Singh filed a missing-persons report with Marple Township Police on Feb. 10, Murray said.
Ten days later, Nadia's body was found inside that Nissan on 30th Street near Chestnut, slumped onto the passenger seat and covered in a duffel bag, according to Lt. John Walker of Southwest Detectives.
Walker said that several parking tickets were left on the car - it had been parked on 23rd Street near Market, but was towed Feb. 14 from that location, a designated snow emergency route, to where police found it because of the coming snowstorm. There's no indication of how long she was in the vehicle before she was found, Walker said.
The official cause of Nadia's death likely won't be released for a few weeks, according to city Department of Public Health spokesman Jeff Moran. That time frame is standard for the necessary toxicology and other tests, he said.
Her brother is adamant that Singh is responsible. He believes that Singh left her in the car- which belongs to Singh's father, Davinder - and skipped town shortly afterward.
"He picked [23rd and Market streets] because it's right near 30th Street Station," Malik said. "He thought he could make a quick escape."
But Singh's family paints a different picture.
Gurjot Singh, Bhupinder's younger brother, said that he often stayed at the couple's house in Upper Darby, that the two had a "really nice relationship" and that his brother went back to Ohio out of desperation.
"Bhupinder really loved her; when she left, he didn't know what to do," Gurjot Singh said in an interview Wednesday. "He went blank and wanted to come see his mother and father; it was the only option he had left."
When asked why his father filed a missing-vehicle report with Solon police Feb. 19, Singh said it was out of concern for Nadia.
"We couldn't find her, and nobody was telling us what was going on," he said.
In the meantime, as Philadelphia police continue to probe Nadia's death, her family is "a mess," according to her brother, and desperate for answers.
"I'm feeling frustrated; we're not seeing the results we would expect," he said.
"We just want more information."
On Twitter: @Vellastrations