Nina Dobrev and Zac Efron are not an item - despite their recent, cozy vacation photos. "Nina and Zac are not dating and have been good friends for over a decade," a source exclusively tells Us Weekly. "Their friends always joke that they should date, but that is not what is going on. They have been there for each other through many phases of life and have always had each other's back." The insider adds that Dobrev, 36, "has been leaning on her family and friends recently" amid her recent split from Shaun White. "[She] has truly felt a lot of love and support," the source continues.