The exes are currently going head-to-head in a heated $50 million defamation trial in which both parties have accused each other of physical and verbal abuse.
Gina and her husband, Stephen Deuters — who is one of the Pirates of the Caribbean star's business partners — have known Johnny for many years and were both close with the former couple during their volatile marriage.
"There was one thing Amber said at the wedding. She kind of leaned into me and said, 'Do you and Stephen ever fight?' I responded, 'We sometimes have an argument,' and she was like, 'No, Gina, like really fight?' And it was kind of unnerving. [I thought], 'Do you enjoy it?'" Gina said in an interview with Page Six.
"I think there is a part of Amber that [believes] fighting is passion. It means there’s sparks, fireworks [in the relationship]," she continued. "[Amber] is someone who is always used to getting what she wants. She is quite entitled and I think she made big demands in their divorce."
She added, "When [Amber] was denied those demands, I feel she was like, ‘I am not going to get what I want so I am going to destroy you.’"
Gina also alleged the All the Boys Love Mandy Lane actress truly enjoyed drama, noting her husband even referred to her as a "sociopathic show pony."
"And he certainly doesn’t regret it," she continued of the derogatory nickname. "Stephen, at the end, was quite literally the mediator … no one else wanted to deal with Amber, and Stephen would be the only person she could talk to."
Gina went on to describe the tumultuous romance as "less of a relationship and more of an Amber invasion."
"Instantly she started moving her friends into his properties," she explained. "It was quite shocking how she eventually isolated him from his family and friends … it definitely felt like we’d kind of lost him."
The bombshell trial is scheduled to resume on Monday, May 16. Closing arguments will begin Friday, May 27.