@Iloveredflagssss I finally found it after 3 hours, the title is so f**g long that it was imposible for me to memorize
Mou Kyoumi ga Nai to Rikonsareta Reijou no Igai to Tanoshii Shinseikatsu
Or in English
A Surprisingly Fun New Life for a Lady Who Was Divorced Because Prince Was No Longer Interested in Her
