I found it in the comment section. C&P
So the prince never liked fl.. because hes the main capture target in a Otome game.. and the reason he married Fl is that the heroin never showed up.. all the concubines have the heroine's traits hence..
Fl dies or it was all a dream and wakes up in bed back when she was still in school..
She goes to school sees the prince (her fiance) trips and gives herself a concussion. While unconscious she remembers her old life and that the ppl close to her were Otome game characters... She voves to let the Heroin take the prince if he fancies her, but still falls in love with him. But uses her "past life" skills to start cooking.. and the prince tries one of the cookies she gave her brother... and he likes it and starts to think FL isnt just a prety face...
https://forum.novelupdates.com/threads/the-love-king-and-his-ornamental-wife.124947/
Read Beware Of The Villainess, The Lady's Butler and Slow Prison Life to calm yourself down.
Before I read the spoiler: Maybe he fell in love with wife's (fl) brother, since he can't confess his feeling to him, that's why he spends the night with other girls (timeline of that time). The only reason why he doesn't be with his wife, he doesn't want to take advantage of her bc of her brother....She will remember her past life that she is in a BL story and make them get together<3
After reading the spoiler: Fxck this shitty husband (╬ ̄皿 ̄)凸