Totally fell into https://www.novelupdates.com/series/the-yandere-came-during-the-night/ and wanted to find similar stories to it. Similarities that I would like: 1) the way MC decided to try to live to the fullest without caring about the real FL (prepared for the worse but didn't scheme against FL until FL decided to scheme her first) 2) the way ML decided that MC is his all the while MC is doing her best to find a husband that is definitely not the ML
Hmm... Maybe The Black Horse Marrying the Soft-hearted Villain Guide To Raising the Sick Villain My Husband With Scholar Syndrome I Lost the Leash of the Yandere Male Lead Our Binding Love: My Gentle Tyrant
Maybe... Greetings, Ninth Uncle. The FL is a Reincarnator who searches for a good, wealthy husband completely failing to notice our ML.