As a female, I find John Donne's persuasion to fall rather flat ("A Vindication: Forbidding Mourning"). First, upon considering the title, I would be rather upset if someone told me that I was not allowed to mourn (actually being forbidden being that much more infuriating). Second, since the entire first stanza exists as a conceit (or metaphor), I feel as if Donne lacks the ability to be frank (straightforward). This said, the text is a poem (which needs to include poetic devices to enhance he language and images). Problematically, if looking at the poem as an assurance, I would not appreciate flowering language or hidden meanings.
As one half of a pair, I would take great distress at being separated from my love. I do not think that anything would ever make a separation like this "okay." I do not think that going on about how much one loves the other, how much one means to the other, or how important the need to be apart would justify a separation. Regardless of how strong the love was/is, time apart would not be acceptable.
The idea that one, especially a woman (who tends to be the more emotional of a traditional pair), needs to be without any protest (sadness or tears) is laughable. While it proves to be wonderful in theory, most women (stereotypically and historically) tend to be the far more emotional one of a pair.
As a woman, I find Donne's persuasion and assurances to be lacking greatly. As a poem, without any reality of leaving behind it, the text proves endearingly romantic. That said, if the poem is meant as a preface to a separation, it lacks any real assurance.