Love is not all by Edna St Vincent Millay

Edna St Vincent Millay 1892-1950

The American poet, Edna St Vincent Millay, was born in Rockland, Maine in 1892, one of three sisters. She specialised in lyric poetry that spoke directly to the senses and brilliantly made use of the Shakespearean 14-line sonnet form. That usually means three quatrains of four lines concluding with a couplet of two lines coming after a pivotal point (known as the 'Volta'), where a stark conclusion is made. This differs in structure from the Petrachian form, that is two stanzas of eight then six lines. This particular poem is actually a bit of a mix of both forms.

Love Is Not All by Edna St Vincent Millay

Love is not all: it is not meat nor drink

Nor slumber nor a roof against the rain; 

Nor yet a floating spar to men that sink 

And rise and sink and rise and sink again;

Love can not fill the thickened lung with breath,

Nor clean the blood, nor set the fractured bone; 

Yet many a man is making friends with death 

Even as I speak, for lack of love alone. 

It well may be that in a difficult hour, 

Pinned down by pain and moaning for release, 

Or nagged by want past resolution's power, 

I might be driven to sell your love for peace, 

Or trade the memory of this night for food. 

It well may be. I do not think I would. 

So what's going on here? What is the poet saying to us with her eloquent iambic pentameter? Clearly she is making the case that, given the basic needs of mankind - food, shelter and health, love is further down the list of wants. It can't provide that roof or clean the blood nor can it "set the fractured bone". The reference to the filled lungs and cleaning of blood is probably a reference to tuberculosis which was prevalent at the time of publication, which was in 1931 during the Great Depression. 
There are, however, elements of the Petrachian sonnet form here. In the eighth line the perspective changes sharply to the first person but then (back to Shakespearean) the final couplet expresses some doubt about what she has previously declared. She might, if necessary, swap this night of love for food but she doesn't think she would. After swaying to and fro she has ended on an ambiguous note.
You can listen to the actress Tyne Daly (of Cagney and Lacey fame) reciting the poem here. There is also a clip of Edna herself reading the poem but her over-dramatic reading is almost too funny for me!