What is Hilary Duff's fear in her marriage? That her hubby, Matthew Koma, will one day cheat and leave her for another woman! The 38-year-old singer dropped a new album, Luck... Or Something, on Friday, where she got super real about a variety of topics - including the rift with her sister and what she worries about most in her relationship! On the track Holiday Party, she struggles with the fear of Matthew cheating on her.