The defamation lawsuit comes after Depp sued Heard for $50m for implying he abused her in a 2018 Washington Post op-ed.
Although she didn’t name him, the Pirates of the Caribbean actor claims Heard’s allegations impacted his ability to work.
Grey, who was briefly engaged to Depp in the late 1980s, reflected on their time together in her new memoir Out of the Corner.
She said their whirlwind romance in 1989 saw Depp propose to her after just two weeks. However, Grey claims he started “getting into trouble” when they were together, having “fights in bars and skirmishes with cops”.
Speaking about the trial that’s currently taking place while promoting the memoir, Grey told Entertainment Tonight: “All I can say about that trial is that it breaks my heart for everybody involved.”
She added: “I just think it’s sad and I wish it was resolved and I just wish everybody well.”
The trial is now on hiatus for a week, and both sides are issuing statements of confidence in how proceedings are going. Follow along with live updates here.
Grey recently told The View that her Dirty Dancing co-star Patrick Swayze apologised to her in tears in order to get her to star in the 1987 film.
The pair had previously worked together on 1984 film Red Dawn, but Grey hadn’t enjoyed the experience.