The TV presenter is currently on trial accused of harassing Anna Larke during their nine-month relationship.
Larke, who apparently told Collins she would "go to the police" and "hurt" him if she wasn't paid the money, described the claims as "absolute lies", according to BBC News.
She told the court: "Oh my God, that's absolute lies. I've never said that. If I had just wanted money I would have gone straight to the press."
Penelope Larke, her mother, added: "He called her all the names under the sun, terrible names. She said he smacked her and swears at her.
"She told me he smacked her in the private parts. I told her it wasn't a very healthy relationship and that she should just pack her bags and come home."
The court previously heard how Collins allegedly made Larke chronicle every sexual experience of her life in a notebook and pushed her into the path of oncoming traffic.
Collins denies harassment, causing fear of violence. The trial continues.