The definition of "resignation" is to have an accepting, unresisting attitude of acquiescence or submission (Random House Dictionary). If the theme of resignation is present in this sonnet, then the first-person poetic speaker will indicate acceptance of her upcoming death and acceptance of the reality of human frailty in upholding intentions. Does she do this?
In the octave, lines 1 and 4, she requests that she be remembered when "Nor I half turn to go yet turning stay." Since we know that the "silent land" is the land of death, we can understand this elusively constructed line to mean: [paraphrase] When I can no longer resist death; when I can not again recover when at death's threshold and turn away from death's face to stay in the land of the living....
The tone here--as displayed by the vocabulary and the sound choices--has no rancor, no bitterness, only quiet and soothing recognition of what is coming: she is accepting of and unresisting toward the approach of death. She is resigned to death.
The analytical details illuminating this quiet, soothing tone are these:
Vocabulary: She chooses simply "remember me," not you must remember, I want to be remembered, say you will remember etc that imply demand or desperation or fear.
Word Sounds: She selects, in the tradition of Edmund Spenser, combination of consonants and vowels that enhance the tone she establishes with her vocabulary: the sounds of the vowels and consonants are open, as in /mem/ /gone/ /land/ /hold/; elongating, as in /m/ /w/ /n/ /lf/ /ay/; soothing, as in /more/ /far/ /n/ /m/; and quiet and quieting, as in /s/ /l/ /lf/ /f/ /-member/.
In the sestet, lines 9 and 10, she forestalls quilt and grief over likelihood that her beloved will, for short moments of time, be distracted from remembering her, although he mourns and grieves his loss of her. She does not speak in a judgmental tone but in a gently consoling tone: "Yet if you should forget..." She requests that he not grieve when the inevitable happens; when human frailty allows distraction and forgetting. She goes further and offers him a consoling solution to the dilemma in the paradox of remembering while forgetting: she attests her words of poetry will remember her. She is resigned to--more than resigned to, she is compassionate of--human frailty in fulfilling intention.
Yet if you should forget me for a while 9
And afterwards remember, do not grieve: 10
For if the darkness and corruption leave 11
A vestige of the thoughts that once I had, 12
Better by far you should forget and smile 13
Than that you should remember and be sad. 14