Did Hussie 'change his mind' or were these relationships never meant to last.

I'm re-reading A5A2 with friends, and i found myself surprised in regards to how much focus is given to certain relationships such as John - Vriska, Terezi - Karkat and to a lesser extent, Dave - Terezi, knowing full well that they didn't last, and the story almost entirely moved away from them. They don't seem to be framed significantly different from Rose and Kanaya, who were stablished in similar ways and kept up their relationship throughout the comic, becoming the flagship 'lesbian couple'. But unlike them, these relationships fizzle out. With Dave and Karkat being focused on very strongly in A6, alongside Terezi's relationship with and mourning of Vriska becoming a central point on her character's development, there's a VERY clear shift. Which makes me wonder, does it feel to y'all like Hussie eventually changed his mind regarding these early pairings, which lead to him breaking them up/making them not work, recontextualizing them and using their fallout to move the characters forward? or were these always meant to be 'temporary' relationships used to show the messyness of the teenage romantic experience, and explore certain aspects of the characters, never conceived as 'endgame' (for what that's worth)?