Kourizatou to Wanruumu Aru Hi Toshishita Danshi ni Hirowareta

When her fiance's affair was discovered, she lost her job, her home, her marriage, and everything else. Itoigawa Momoka is the type of person who can accept unpleasant things with a smile. The only thing that makes her happy is being in a relationship with Komatsu, a university professor she met at the bento shop where she works. Komatsu is transferred to Germany, and Momoka asks him to come with her. In preparation for married life abroad, she cancels her lease on her house, quits her part-time job, and just as she's waiting for her flight the next day, she witnesses her fiance's affair. At the same time, her true nature as a bully and emotional abuser is revealed. Wandering the streets in despair, Momoka is picked up by an unsociable university student who buys her a different bento every day. A woman in her 30s living with a clumsy younger man begins her life together! https://www.cmoa.jp/title/315354/