The comic book version of Sharon has long been the love interest of Captain America, but was also instrumental in his death following Marvel's Civil War arc, though she was under the control of the nefarious Doctor Faustus at the time. Sharon has been an integral part of S.H.I.E.L.D., serving, at one point, as the Executive Director of the agency. Sharon recently sacrificed herself in order to help Rogers escape Dimension Z.
Emily VanCamp will take on the task of bringing Agent 13 to life in Captain America: The Winter Soldier and, according to director Joe Russo, they plan to bring at least a little bit of the comic book romance between Rogers and Agent 13 to the film. In an interview with Nylon magazine, Russo stated when casting Sharon Carter they "wanted someone that Cap would have an immediate interest in," and that VanCamp's work on the ABC series, Revenge, "was a great test tube for what the character could be."
While we have all likely seen the shots of Cap getting intimate with the Black Widow, it seems as though there may be some action in store for Agent 13. Really, there are so many unknowns with this film at this point, despite it being named after a very popular comic arc, that it's hard to say exactly where Agent 13 fits. It's certainly a possibility that we see the Death of Captain America story play out in the future and perhaps Agent 13 will pull the trigger. What are your thoughts about her role in the MCU?