Her Cardboard Lover (1942)

Songwriter Terry Trindale (Robert Taylor), who has a crush on Consuelo Croyden (Norma Shearer), racks up a large gambling debt to her while trying to gain her attention. To pay it off, she proposes that he pretend to be her lover, in order to make her former beau, Tony (George Sanders), jealous. Terry gladly accepts the offer and performs his duties with dedication, hoping that Consuelo will start to like him better. But, the more he keeps her from Tony, the more she seems to want Tony.