Jean Valentine (b. 1934) taught at New York University until 2004. Since then, she has hosted many poetry seminars. She is the author of several poetry collections and the recipient of many prestigious awards, including the 2009 Wallace Stevens Award. A detailed biography may be found here:
The poem is an elegy to Ms. Valentine's dear friend. It is organized in three stanzas, the first two of four lines each, and the last of six lines--therefore, there is at least a nod to the Italian sonnet form. However, the title is "Friend,"--the word "Friend" followed by a comma. That comma is crucial, as it makes the title play a simultaneous role as a first line, as in the opening of a letter, "Dear Friend,". So, the poem may also be viewed as a letter. This is perhaps what the poet intended, as she reveals in her notes that it was a letter from Ms. Rich that sparked their intimate, years-long friendship.