In Vanilla Sky, Cameron Diaz played Tom Cruise's crazy obsessed ex-GF. (Weird, we know.) Well, it seems like Cam is back to playing that role again -- this time, off-screen. Spies for Page Six report that Cameron's totally not over ex, Justin Timberlake, and her behavior after the Golden Globes proved it. The smitten actress followed her ex to the In Style after party, where insiders say, "they had an awkward conversation." Still, Cam wasn't deterred, so she chased him to the Universal party and saw something that no girl wants to see -- her recent ex chatting up another female. So when she spotted Justin talking to Jessica Biel, Cameron "blew up" at her. Aw, Cam -- we know it hurts, but that's really no way to get your sexy (ex) back.