Evidence
Detective Boney has gathered enough evidence to prove that Amy has too many holes in her story for her to be telling the truth. Ironically, the FBI demands that she stand down, and in doing so Amy is let go. Regardless of the evidence Boney sees, she can't prove any of it definitively.
The Truth
Nick is prepared to go public with the truth of Amy's faking her disappearance and murder. Ironically, he doesn't as Amy is pregnant with their child and he chooses to remain with her, even announcing to the world on television that they are pregnant.
The Man
Amy left Nick because he was cheating on her, and she plotted to destroy his life with her plan. Ironically, she returns home to him because she sees him on a talk show being the man she knows he is supposed to be.
Nick
Amy has disappeared and it appears that she was murdered from all of the evidence. Ironically, Nick responds apathetically to this evidence. Ironically as well, this causes him to be painted as a sociopath and he becomes the prime suspect in his wife's murder.
Desi
Amy "escapes" Nick with the help of Desi, a man she filed a restraining order against years prior. He believes that he is her knight in shining armor; ironically, she kills him and makes the world believe that he kidnapped and raped her in order to get back to Nick.