«Lo! as a careful housewife runs to catch
One of her feather’d creatures broke away».
The image of an errant mistress chasing chickens while neglecting her infant suggests a love triangle between the woman, the young man, and the poet.
Lo! as a careful housewife runs to catch
The youth is “one of her feathered creatures” and the poet “her babe.” Incredibly, and almost pitifully, the poet again begs the woman to love him; he seems to have regressed to a baby needing its mother for shelter and support. To add insult to the poet’s injury, he learns that the youth has tried to avoid the woman, but she pursues the youth: “But if thou catch thy hope [the youth], turn back to me / And play the mother’s part, kiss me, be kind.” So long as the woman sexually favors the poet, he will disregard her pursuit of the young man, which is the same argument that the poet makes in Sonnets 135 and 136.
However, here in Sonnet 143, he states his request unequivocally, mincing no words about what he wants and how far he is willing to go to get it: “So will I pray that thou mayst have thy Will, / If thou turn back and my loud crying still.”
English audio from YouTube Channel Socratica
Summary from Cliffsnotes.com