I cannot find a death record for Owen in Kentucky. It should be some time between 1920, when he was listed in the census, and 1930, when Nora was listed as a widow.

1900 census of Bath Co., Ky, lists Owen Crosewhite, 21, b. Nov 1878, single, as a boarder with Alfred Alley, age 45, son of Afred Alley Sr. and Martha Crouch.

Her death certificate records Nora Mae Crosthwaite, age 77, born 14 April 1868 in Ky, widowed, late husband Owen Crosthwaite, died 30 Sep 1945 in Clearfield, Rowan Co., Ky, father Joseph McKinney, mother’s maiden name Cordelia McKinney, cause of death chronic myocarditis, informant Kenneth Carey, Morehead, Ky, burial in Bath Co., Ky.

Rowan Co. marriage register Book A records on p. 116 the marriage of Owen Crosthwait and Nora Carey on 9 Feb 1907.

1910 census of Rowan Co., Ky, Pearcy precinct, p. 234B, enumerated April 23, lists as household #104, family #111:
Crosthwait, Owen, 31, farm owner; Nora, 42, wife; married 3 years, mother of 6 children, 5 living; Carey, Cecil, 20, step-son; Virgil, 18, step-son; Zona, 12, step-daughter; Kenneth, 8, step-son; Sherman, 2, step-son. Owen’s father is recorded as born in Alabama, all others in Ky. (The notation of Sherman age 2 as a Carey and a stepson is not consistent with the number of years married nor with the 1920 census, which lists him as Crosthwait.)

1920 census of Rowan Co., Ky, Pearcy precinct, p. 216B, Clay Lick Road, lists as household #119, family #127:
Crosthwait, Owen, 41, general farming; Nora, 50, wife; Sherman, 11, son; Ruby, 9, dau; Cordia, 7, dau; Carey, Cecil, 29, stepson; Zona, 22, step-dau; Kenneth, 18, step-son. All born Ky Ky Ky.

1930 census of Rowan Co., Ky, McKinzie precinct, enumerated 12 April, lists on p. 2A as family #92:
Crosthwait, Nora, 61, widowed, age at first marriage 20, farmer; Sherman, son, 22; Ruba, dau, 19; Cordia, dau, 17. All born Ky Ky Ky.