Sadie Dunhill is a character in Stephen Kings 11/22/63. She is a librarian at a high school in the small town of Jodie, Texas. She had a relationship with the novel's protagonist, Jake Epping. She originates from Georgia, but moved after separating from her husband. She is 6', and is known for being self conscious.
Sadie Dunhill was previously married to John Clayton, an abusive husband who suffered from extreme OCD. She previously lived in Savannah, Georgia, but moved to Jodie, Texas, after her divorce. She is set to replace "Miz Mimi," as the high school librarian. (She also voted for Richard Nixon in 1960.)
Sadie meets Jake, "George" Epping in the early 1960s. She understands there is something different and mysterious about him, but doesn't learn he is from 2011 or 2016 (in the Hulu miniseries) until late 1962. She insists she help him save John Kennedy's life, despite Jake's protest.
Sadie initially breaks up with Jake, because of the lack of transparency about his past. She eventual accepts this, when Jake calms her down by predicting accurately how the Cuban missile crisis will end. She was suicidal during the whole event.
While in a relationship with Jake, Sadie's ex-husband John Clayton, shows up. He had apparently been stalking her, and he slashed her face. He then commits suicide. Sadie spent time in a hospital, and had multiple plastic surgeries. This leads Jake to consider telling her about modern medicine, and how her face could be fixed. She figures out on her own, where Jake is from. Sadie is always self conscience, and almost refuses to accept "charity," or a benefit performance, to pay for her facial reconstruction surgery.
After Jake is injured by three mob henchmen, Sadie spends time taking care of him, like he did for her after her face was cut. She tries to jog Jake's memory, for several months. She finds him on 11/22, after figuring out he was lying about his memory to keep her safe, and helps him stop Lee Harvey Oswald. Unfortunately, Oswald shoots her in the process. She dies after telling Jake, "how we danced." Jake is determined to go back through the time portal to save her, and redo the past five years of his life.
George, upon learning he has to undo everything he did in the 50s and 60s, resets the timeline. In this alternate timeline, where she never meets Jake, her face is still slashed by John Clayton. She never remarries, however. She goes on to have a career in local politics, and charitable work helping out the mentally challenged and disenfranchised.
In 2012, Jake finds a news article about her. She is now 80 years old, and is still living in Jodie. Jake travels to her, and she asks where she knows him from. Jake responds that she knows him in another life. They share one final dance to Glen Miller's, In the Mood.