From the Wikipedia reference to Fanny Crosby:
(Alexander Van Alstyne is her husband)
Van Alstyne rarely accompanied Crosby when she traveled, and she vacationed without him.
 Despite living separately for more than two decades, Crosby insisted that they "maintained an amiable relationship", kept in contact with one another, and even ministered together on occasions in this period. For example, Alexander played a piano solo at the third annual reunion of the Underhill Society of America on June 15, 1895, in Yonkers, New York, while Crosby read an ode to Captain John Underhill, the progenitor of the American branch of the Underhill family. Her only recorded admission of marital unhappiness was in 1903 when she commented on her late husband in Will Carleton's This is My Story: "He had his faults—and so have I mine, but notwithstanding these, we loved each other to the last".
From Genealogist Harry Macy, Jr.:
Fanny Crosby's "Ode to the Memory of Captain John Underhill 1597-1672 and to the Honor of His Descendants" is reprinted on pages 32-34 of volume 2 of the genealogy. It says it was read by the author at the Society's meeting in Yonkers in 1895.
We now know, of course, that 1597 was an error and he was born 1609.
Volume 2 is available online to subscribers to Ancestry.com. Perhaps the Ode was published in the Society's Annual Report for 1895 which might be available at FamilySearch.org, but I haven't checked for that.