Inga no Hana: Fukushuu Furin Onna to Tsumi Darake no Sarezuma

Rino is a 34-year-old housewife married to her kind husband, Takumi. She basically has a picture-perfect marriage. However, one night, the topic of having kids is brought up again by Takumi. Rino has a secret that's holding her back from getting pregnant... In the past, she left her infant daughter at an orphanage's doorstep. Her mother-in-law is laying on the pressure to have a baby, and Takumi is irritated with her. Not only that, Takumi goes drinking with the new part-timer, Hina... (Source: MangaPlaza)