The sad reality that most starfags comstantly try to deny, Daron was not developing anything new, she inspired herself or plainly ripped off (whichever you prefer) common anime tropes, romance beimg that the main character and "the one that the guy in the show should pic" has to endure a time of sadness because said guy thinks he loves someone else.
Usually that kind of story gives us clear signs that the relationship is just not working, the guy likes a thing that the girl dislikes completly, the girl has a hobby that makes the guy feel insecure, jealous, or whatever excuse you can think of, anything to make it clear that both are not exactly for each other.
But in SVTFOE, we have them working nicely, Jackie decided that their date night was not gonna be ruinned by the event being shitty, and says it out loud. It was a mistake to go to that dance because it was terrible, so they better go on their own and let their feelings flourish in other way.
Can you imagine if they danced? I feel like a moon would have disintegrated as they would have broken the curse in other way.
What's really sad is that part, they made them work as a couple, they didn't have any troubles until season 3 came in and forced them to break up, that was really such a retcon, Marco had so many more experiences to share, but the curse made him obsesses with a meaningless week in shit-fest royal country.