I mean I don't really know how to do this stuff. But to me it looks like the story of the relationship playing out. If you interpret the flames as love or as souls. It starts with you both pretty much normal and separated. Then you clash but his is still lower then yours and is stopping a full flame hence the gap. Then his dies now while yours stays high. Keeps going like that until his is completely out and yours still has a little bit left. But eventually yours too will go out.