The action begins with the main character, Ramatoulaye, writing to her close friend in America, Aissatou. Ramatoulaye tells her correspondent that her estranged husband, Modou, died suddenly of a heart attack and that she was deeply affected by his passing.
In her second letter, Ramatoulaye described the funeral procession and how she was forced by custom to receive in her house her husband’s second wife, Binetou. The two women received their husband’s friends and family but remained behind when Modou’s body was taken to his final resting place. Ramatoulaye writes that she was married to her husband for 30 years while his younger wife was married to him only for five years.
The people who come to the funeral procession give gifts of money to the family but Ramatoulaye notes that her share will be much smaller than the one the other family members will get. When the guests leave, Ramatoulaye’s house is destroyed. Ramatoulaye notes however that she has just started the grieving period required by her religion. During that period, the family also tries to reveal the secrets the dead man hid away from them and to understand who he was in reality. Binetou and her mother try to profit from Modou’s death, and claim that a house Modou owned belongs to them.
Ramatoulaye is less interested in her late husband’s finances and more interested in the reason why he chose a much younger wife. Ramatoulaye had twelve children with her husband, but that didn’t stop him from marrying a 17-year-old girl.
In her sixth letter, Ramatoulaye recalls how she meets her husband while on a trip. They fell in love but shortly after that Modou had to leave for France to study law. They continued to correspond through letters regularly and when he returned they decided to get married despite the fact that Ramatoulaye’ mother was against the union. She also mentions the fact that she was courted by a doctor named Daouda, considered by her parents as being a suitable match for her, but that she rejected him.
Next, Ramatoulaye talks about her friend Aissatou and the marriage she secured for herself. Aissatou married a man considered by many as being above her. The two friends get married around the same time and they quickly discover that being married is far from what they expected it to be. Both women find that their families expect them to take care of the house singlehandedly while also having a professional career. Despite this, the two women continue to be friends and to spend time together contemplating life.
Modou becomes the head of the union in which he is a member of shortly after getting married and he seems to be against the globalization that affected Senegal as well as other African countries. He believed that globalization will affect negatively the country and that his country will end up without a national identity.
Then, Ramatoulaye talks about how Aissatou's mother’s-in-law refused to accept her as a match for her son. The mother thus took a young woman under her wing and took care of her until she reached adulthood. Then, she pressured her son to marry the young woman, claiming that he would bring shame to the family if he refused. Aissatou's husband agreed to marry the other woman, and while Aissatou continued to cohabit with him for a while, she left him after the new wife became pregnant and began having children. Aissatou chose to focus on her education instead and was offered a job at the Senegalese consulate in America shortly after leaving her husband.
In the thirteenth chapter, Ramatoulaye talks about her daughter and her daughter's friend, Binetou. Binetou once told Ramatoulaye that her parents wanted her to marry a sugar daddy but that she didn't want that for herself. Ramatoulaye later found out that Binetou’s sugar daddy was her own husband. Ramatoulaye, however, remained calm and tried to do her duty as a wife.
When Ramatoulaye’s daughter, Daba, found out that her father was going to marry one of her friends, she insisted her mother leave him, just like Aissatou did with her husband. A fortune teller also told Ramatoulaye to leave her husband but she refused, thinking that she was too old to get married again. Despite being affected in a negative way by the news, Ramatoulaye decided to remain with her husband.
After the marriage takes place, it becomes clear that Binetou is not happy and she drowns her unhappiness in lavish things and riches. Binetou’s mother is also interested only in her son-in-law's money, and the two women spend excessive amounts of money regularly.
After a while, Ramatoulaye agrees that it is best if she leaves her husband even if that means learning how to survive financially on her own. When Ramatoulaye tells Aissatou that she and her children must rely on public transportation, she buys them a car and Ramatoulaye learns how to drive it in a short period of time. Despite all the hardship she has to endure, Ramatoulaye continues to be faithful to her husband and even blames herself for the fact that he left her for another woman.
In the eighteen letter, Ramatoulaye writes that one of her dead husband’s brothers, Tamsir, came to her and proposed to marry her, claiming that he would rather marry an old woman than marry the young Binetou. Ramatoulaye rejects him however, claiming that the only reason he is interested in marrying her is because he wants his brother’s wealth. The next day, another man comes, Daouda Dieng. Ramatoulaye knows that he wants to propose to her as well so she starts talking about politics instead and he doesn’t mention the marriage proposal anymore. The next day, Daouda Dieng returns and made his intentions known, claiming that he never stopped loving her. After leaving, the woman who predicted that Ramatoulaye would marry again comes to her and tells her she was visited by her next husband. Despite knowing that Daouda will be a suitable husband and a good father to her children, she decides that she does not love him and thus she cannot marry him. She also argues that she knows what it feels like to be pushed to the side by a second wife and she didn’t want to create any pain for Daouda’s first wife.
More and more suitors come to Ramatoulaye but she rejects every one of them, knowing that the only reason they want to marry her is because she became a wealthy woman after her husband’s death. Ramatoulaye rejects every suitor that turns up on her doorsteps. Instead, she is helped by her children, who take care of her and help her raise the smaller children she has in her care. While she is proud of her children, she is also worried that she gave them too much freedom and that they are too rebellious. Despite her fears, Ramatoulaye does not try to control her children and instead lets them make their own decisions. One of her children gets pregnant out of wedlock but instead of getting angry and responding in a violent way, Ramatoulaye embraces her daughter and shows her love and support.
Ramatoulaye meets with Ibrahim, the man who got her daughter pregnant, and is pleasantly surprised to see that he is more than willing to accept responsibility for what happened and take care of the baby. Ramatoulaye feels better, knowing that her daughter is in good hands.
From that point on, Ramatoulaye decides to talk openly with her children about sex, and instead of trying to convince them that abstinence is the only way, she talks with them about safe sex and how important it is to be responsible when having sexual intercourse.
In her last letter, Ramatoulaye reveals that Aissatou will soon come to visit her, and she expresses her excitement upon hearing this.
