Actress Michelle Williams is dating director Phil Morrison just weeks after splitting with her fiance Heath Ledger, according to reports. Brokeback Mountain co-stars Williams and Ledger, who have two-year-old daughter together, ended their engagement last month (Sep07). And American magazine Star is reporting Williams is stepping out with her longtime friends, Junebug filmmaker Morrison. An insider tells the publication, "(They) are being cautious, because they know Michelle is just coming off a serious relationship - but it's hard to take things slow when you're having so much fun."