It would appear that Guthrie Smith never married.
Tracking him backwards through time, he was single in 1930 and 1920 Sante Fe-newspaper editor;in 1918 he reg. for the WWI draft in Santa Fe,and worked for the "New Mexico Council for Defense" in the Capitol building;his birth date given as Apr.12,1877;he gives his brother "Dr.Henry H.Smith" as his next of kin, but says he does not know where he lives.
In 1910 he lived in Alamogordo,NM and was the editor of the paper there. In 1900 he was in Alabama. In 1880, he was living in Selma,AL with parents Henry H.Smith,age 33 born NC,and Mattie G.Smith age 35,born MS;Henry was a minister. There is a daughter "Freddie" age 17 born in MS-one assumes from previous marriage of Mattie given the age disparity in children; and Guthrie age 3 born in AL and Henry H.age 1 born in MS.
Guthrie is buried in Fairview Cemetery in Santa Fe, but I was unable to find a death date for him. After 1942 probably, as his listed in a city directory in that year.