The relationships depicted in Robert Browning's "My Last Duchess" and Elizabeth Jennings's "One Flesh" are drastically different. 

In Browning's poem, the speaker, the Duke, is telling the story of his "Last Duchess" to the representative who is helping to arrange  his new marriage. The Duke had a strained relationship with his late wife. She was kind and cheerful to all, but the Duke resented her friendliness: "...as if she ranked / My gift of a nine-hundred-years-old name / With anybody’s gift." He also distrusted her actions, and he became more and more controlling: "...I gave commands; / Then all smiles stopped together." The Duke then blithely tells the representative that they should proceed with the arrangement for his new marriage. The suggestion is that the Duke, who reveals an instability and desire for control, murdered his last duchess. Now, her image hangs on his wall "as if alive," where he can perfectly control her.

In Jennings's poem, the couple are described as "Strangely apart, yet strangely close together, / Silence between them." The husband and wife are still alive and still married, yet they sleep separately and are described by the speaker as no longer having an emotional or loving connection: "...These two who are my father and my mother / Whose fire from which I came, has now grown cold?"

The dynamic Browning presents is a psychologically and physically abusive one. The dynamic Jennings presents is emotionally confining and stunting, loveless and adrift, but it is not abusive; it seems that the couple in her poem remain married of their own free will and have no malicious intent towards each other. Browning's Duke is nearly guaranteed to be as awful to his new wife as he has been to the last (and to any wives who came before her!).