Lena Dunham Reveals Affair and Breakup in Famesick

Lena Dunham’s new memoir Famesick, released April 14, has quickly become one of the most talked-about celebrity books of the year, driven largely by its candid—and at times uncomfortable—revelations about her past relationships, health struggles, and life in the spotlight.

At the center of the book is Dunham’s account of her five-year relationship with musician Jack Antonoff, which lasted from 2012 to 2017. For the first time publicly, she admits that she was unfaithful during the final stretch of their relationship. According to Dunham, the turning point came after a heated argument about her reliance on prescription pain medication. She claims Antonoff flushed her pills during the dispute, an incident that left her feeling destabilized and resentful.

That same night, she reconnected with an old school acquaintance identified as “Nick,” and the two began a brief affair that continued for about a week while she was still living with Antonoff. After the breakup, Dunham says she became briefly engaged to Nick before entering treatment for substance dependency and ending that relationship as well.

The memoir also revisits long-circulating rumors about Antonoff’s close working relationship with a young pop star—widely presumed by readers to be Lorde, though Dunham does not name her directly. Dunham describes feeling increasingly sidelined as Antonoff spent long hours in their home studio with the singer. In one scene, she recalls returning from a medical appointment to find the artist lying on their couch, crying, while Antonoff comforted her. When Dunham expressed discomfort, she writes that Antonoff dismissed her concerns, suggesting she was jealous of their friendship.

Beyond her relationship with Antonoff, Famesick includes a series of other striking claims. Dunham alleges that her Girls co-star Adam Driver displayed volatile behavior on set, including an incident where he allegedly threw a chair against a wall and punched a hole in his trailer. She also recounts an uncomfortable personal interaction in which he purportedly refused to leave her apartment during a visit.

In another section, Dunham describes receiving an invitation to what appeared to be a women’s empowerment group during the early days of Girls. She later came to believe the invitation was tied to NXIVM, the now-defunct organization widely described as a cult, and says the outreach came from actress Allison Mack, who was later convicted for her role in the group.

The memoir also delves deeply into Dunham’s ongoing health issues, including chronic pain, a hysterectomy, and her eventual decision to seek treatment for prescription drug dependency. These sections are among the most detailed in the book, presenting an unfiltered account of how her physical and mental health intersected with her career.

Timed to coincide with the 14th anniversary of the Girls premiere, Famesick is structured as a reflection on Dunham’s rise to fame and the personal consequences that followed.