Mrs CCB went to watch Last Christmas last night (not her choice, she’d hasten to add). The film is loosely based around songs by Wham! and is kind of silly enough until then end when you find out that the male lead is actually a dead person who, literally, gave his heart - via organ donation - to the female lead after being killed in a road traffic accident. Hence "last Christmas I gave you my heart
I laughed so hard when Mrs CCB was explaining this.