Clare's mother, Lucille Abshire, is a very troubled, unpredictable woman. During her first date with Henry in the present, Clare explains, "My mother is kind of off in the clouds." Lucille has never been much of a mother to Clare or her other children. Although the woman's a passionate gardener and poet, she remains emotionally aloof and never shares her work with anyone.
After Lucille has a nervous breakdown during a family dinner, Clare reveals to Henry that her mother is manic-depressive and that she tried to commit suicide after losing a child. Clare very much struggles with her mother's emotional aloofness, and when Lucille dies of cancer, Clare feels especially lost because she believes she never really knew her mother. When she discovers a poem dedicated to her in her mother's belongings, Clare finally understands that, despite her emotional distance, Lucille loved her very much and respected her choice to leave home to live her own life.