Godwyn said that the singer was left devastated after her grandmother Cynthia lost her battle with breast cancer in 2006.
He further said that it was a big lost for the Rehab singer, as her grandmother had been the one person she depended on.
Godwyn even said that Cynthia was the only one who could control the 24-year-old's behavior.
"Cynthia was the one person who could make Amy behave and who she would listen to," Contactmusic quoted Godwyn as saying.
Winehouse's father Mitch backed up Godwyn's claims.
"Cynthia was more like a best friend to Amy. She kept her feet on the ground. After she went, there's nobody who she'll listen to. She certainly won't listen to me," he said.