Read it and weep, guys: Jennifer Aniston is nearly all locked up. She and beau Justin Theroux are engaged. Aniston made Justin's 41st birthday celebration last week particularly special when she gave him the "extraordinary gift of accepting his proposal of marriage," a rep for Theroux tells People. The two first locked eyes when they starred together in Wanderlust, and have been an item for more than a year. Justin, a director and screenwriter as well as an actor, is the son of novelist Paul Theroux.