Juanita Natasha Kinsey, 37, was burned over 40 percent of her body, her family said. She was in the Jaycee Burn Center at University of North Carolina Hospitals in Chapel Hill.
Police were trying to find Timothy Kinsey, 43, whom they believed was in Lenoir or Jones County.
Juanita Kinsey's 14-year-old son, Timarcus Carraway, who lived with his mother, was also burned when gasoline splashed on him and when he used a coat to try to put out the flames burning his mother, he said. He was treated for burns on his hands and arms and released from the burn center.
The attack happened early Saturday at 713 Lincoln St., police said.
Juanita Kinsey is a shelter coordinator for SAFE of Lenoir County, which supports victims of domestic violence and sexual abuse.
Tierra Carraway, Juanita Kinsey's daughter, said she had spoken with her mother shortly before the attack. She had said she wanted to visit her mother with Juanita Kinsey's grandchildren, but her mother said she was concerned by Timothy Kinsey's behavior and did not want the children to visit then. She also asked her daughter to stay by the phone, Tierra Carraway said.
"What this person did to his wife is disgusting, and I don't understand it, and that's the reason we're putting forth all effort possible to get the word out and get this person off the street," said Kinston police spokesman Woody Spencer.
Timothy Kinsey has served time in state prison for receiving stolen property and for drug possession, according to state records.
The mobile home sustained moderate damage in the fire, authorities said.