Alice Stern is the central protagonist of This Time Tomorrow. At age 40, Alice takes stock of her life: She works in the admissions office of the private school she attended, a job she’s had for decades without ever intending to make it into a career. She wanted to be an artist, a dream that never panned out. She’s single and childless, though she believes she is happy on her own. Her friends have mostly moved away, had children, and established family lives, leaving Alice largely alone. She struggles with the impending and slow death of her beloved father, Leonard.

While Alice’s reflections on her life are mostly positive, she comes to realize that she has rarely sought anything out and has instead settled for the circumstances she finds herself in. She is notably un-impulsive as an adult. Her rejection of Matt’s proposal is one of the few life-altering decisions she has deliberately made, and the first of many in the book. She frames this rejection as her right to choose what she wants out of life rather than go along with what society might expect of her, a right she is able to pursue much more dramatically in her subsequent time travels.