Cara Santana is dating Shannon Leto after her split from Jesse Metcalfe, a source confirms to Us Weekly.The actress, 36, and the Thirty Seconds to Mars drummer, 50, were spotted kissing and holding hands in Santa Monica on Monday, August 17, in photos published by the Daily Mail.The news comes nearly seven months after Us exclusively revealed that Santana and Metcalfe, 41, had called off their three-year engagement and 13-year relationship.