I think i remember the wrong story...
Then which manhwa is it where the plot is similar but the FL waste no time to divorce her cheating husban, get the title of the head family back and kick her ex husband and his mistress out of the house and they need to survive with no money and gamble addiction and then the ex husband started to think hes the one that got cheated when FL find some deserved good dude
Both the knight and the chosen prince giving ML vibe i have no clue which one is it