"She is absolutely not okay with him dating Miley," an insider source told HollywoodLife.com. "It's getting really messy now. It's got her very upset."

The Hollywood Life insider claimed "Still Alice" actress is very concerned about the relationship she has decided to take matters into her own hands. The source said, "This is putting a huge strain on the holidays for Maria, she's so worried where this whole thing could lead Patrick."

The source continues, "Maria is planning have a one on one with Patrick over the holidays because she wants to talk some sense into him."

Miley has been single since the breakup from music producer Mike Will Made It earlier this year. She was engaged to actor Liam Hemsworth, but later on, both of them ended the relationship in September 2013. While Patrick split from girlfriend Taylor Burns earlier this year after a two-year relationship.