There was only one reason Fil agreed to film the music video: that was to incite jealousy or any unpleasant feeling in those with whom she wanted to watch it. It was more like a mind game. The storyline was a bonus. The twist of the story was that they weren't actually lovers. But rather, best friends.
The song and the music video were all about a man in love with his friend. All the scenes where they appeared as typical lovers were just them being friends. Fil's role was committed to someone else, and her actual lover was cheating on her. But alas, even though she knew about it, she never told anyone about it.
Hence, the dilemma in their friendship.
Anton's character wanted her but didn't have the guts to say it to her face. All he could hope was for Fil and her lover to break up. Meanwhile, Fil's character stays in the relationship out of love. Even though this love was taking pieces of her heart.
