Why do fandoms always ship the aroace coded character with someone who they HATE?

Like I headcanon a lot of character as being aspec, even tho it may or may not be me just projecting cus we act a lot alike, and then they end up dating someone and being suuuuuper lovey dovey, mwah mwah mwahhh, I love you so much babe *insert 50 billion heart emojis*, as if they didn't just hate each other like two minutes ago?

Idek if that made any sense help