Brokeback Mountain co-stars and Academy Award nominees Heath Ledger and Michelle Williams might be headed for a break-up in the near future. The New York Daily News is reporting that the two lovebirds, who share a child together–17 month old Matilda–had a huge argument after Heath was spotted around a hoard of women on Valentine's Day at a popular L.A. night club called Teddy's.

Reportedly, he wasn't doing anything too inappropriate but some say Michelle is still very angry with him for going out and partying on Valentine's Day while she sat home with the baby.It's possible things have cooled down between the two of them since they were spotted on the red carpet together this past Oscar weekend at the Independent Spirit Awards.

Ledger's next upcoming project is a film called I’m Not There where he, Cate Blanchett, Richard Gere, and Christian Bale will all be playing music legend Bob Dylan. The film is written and directed by the brilliant Todd Haynes, and Michelle Williams is also starring the project. After that he's playing The Joker in the next installment of the Batman franchise called The Dark Knight, where he will again co-star with Christian Bale, along with Michael Caine, Gary Oldman, Aaron Eckhart, and Maggie Gyllenhaal.