Food was not enough. Ariel had thought that it would be all it took to show Tristan that she had romantic feelings for him, but it just wasn't. She was coming up with dish after dish, and making memorable meals for Tristan.
But while Tristan was obviously grateful for the food. It was clear that he did not get the meaning behind it.
He just had not picked up on the fact that almost every new dish that Ariel had made for him had been heavily centred around aphrodisiacs. At the end of the day, Ariel was only human.
She could not just stand by, watch her husband eat foods that were supposed. to get him to see her in a new light, and just offer her a simple thank you, then be on his way without feeling dejected. But despite her disappointment that her not so subtle use of food had not worked, Ariel was not giving up.