“Weeds” star Mary-Louise Parker and former flame Billy Crudup seem to have mended fences since their breakup seven years ago. Crudup left Parker for Claire Danes while Parker was pregnant with their son, William. But this weekend, Crudup, Parker and her new boyfriend, musician Charles Mars, took William to the DR2 Theatre in Union Square to see “Dear Edwina.” The adults remained cordial but avoided taking pictures together. Parker also hung out at the show with Brooke Shields, who was there with her two daughters.