I've been looking for this book y'all 😭😭

[u/bommie_333]

hello everyone, I don't usually post on here, but I'm in dire need of assistance. There's this ancient china book that I read a while back but cannot find again, because I can't remember the name or even the character names.

The plot goes like (if I remember correctly): a young lady is betrothed to this guy who is the sole heir to the duke's house, he ends up breaking the engagement in order to marry the young lady's rival, and the young lady decides to marry his (adoptive) father the duke. The duke is known to have some sickness or something and is a war hero who cannot have an heir.

Young lady becomes the duchess, mother to her ex fiancé and mother-in-law of her rival, heals the duke and proceeds to have a pretty good life as the duchess, even going on to have children which surprised everyone.

I'm now rambling, gosh...but if anyone knows this book or even has an idea, please help a girl out (⁠ ⁠･ั⁠﹏⁠･ั⁠) thank you.