Help i forgot what was said and done
I had to go back and re-read. SO, with the NEW context, the situation seems to be: when the MC was choosing to corrupt his vassals / make them stronger, he was also able to make a love confession. Boy was over there playing this empire sim like an otome game, and he chose to say "I love you" to the grand duke. But the guide interfered, and what the grand duke heard MC say was "I hate you." So the grand duke was GUTTED and told the MC that he despised him too. And then our MC was so upset about being rejected by his 2D husband, he quit the game.
Damn... That biaach of a guide
So you're the fucker that caused the rift in their relationship. This son of a b*tch just can't mind his own business he has to interfere in someone else's love confession. ಠಗಠ