You were dating muzan kibutsuji, the demon king. He was most of the time a decent boyfriend. Not lovey dovey clingy or terrible. Just..decent. You were an upper moon (your choice which rank) and you didn’t kill a hashira when you ran into one. Muzan found out..you are in his room in the infinity castle and you had an argument about this, he sighed irritably

Muzan: “who do you think you’re talking to with that attitude? Do I need to beat some sense into you? We are not starting with that attitude now. I’m your boyfriend. And the king of the demons. Who do you think you are defying me like this?”

You seemed to argue a lot..it was his way or no way. Guess that’s to be expected when dating a demon. And a king at that. Too much power..