Describe the form and meaning of "Remember."

"Remember" is constructed as a sonnet. The sonnet form can do a lot to help us understand the somewhat elusive meaning of "Remember." The sonnet form, in this case, the Petrarachan form (not Shakespearean nor Spenserian) tells us several important things:
The volta of line 9 turns the sonnet toward the presentation of the paradox underlying the sonnet and the paradox in the resolution.
The sonnet problem and resolution are presented in the sestet, last 6 lines, of the sonnet.
Three ideas, including a problem, and a resolution are presented as subdivisions of the theme of the sonnet.
The first 8 lines, the octave, presents the point argued while the last 6, the sestet, present the counterpoint argued and the resolution paradox.
The last six lines, the sestet, seems to present some problems for readers. Line 9 is what is called the volta. The volta is where the sonnet turns form presenting the first two thematic ideas to presenting a problem and solution, usually a paradoxical one.
So then, what's happening in the volta of line 9, "Yet if you should forget me for a while (9)," is that the sonnet turns from the point argued in lines 1-8 and turns toward the counterpoint argued in 9-12. The point of this very complexly organized sonnet is: "Remember me" after I have gone "into the silent land" of death. The counterpoint is: but if you "forget me" [for awhile], my poems remember me, so smile. Voltae most often start with conjunctions of opposition, often "yet" "but" or "and yet." Line 9, the sonnet volta, introduces the counterpoint argument with the oppositional conjunction "Yet": remember me yet if you forget me.
Troublesome Phrases
Before going further with the analysis of lines 9 through 14, it is important to explain the meaning of some troublesome phrases, three in the first 4 lines of the octave and four in the sestet:
Phrases to Explain
Lines 1-4into the silent landhalf turn to goyet turning stayLines 9-14for a while darkness and corruptionvestige of my thoughts
Line 2: "into the silent land"
In Christianity, there is a long history to the phrase "into the silent land." In 1597, the phrase was used as the title for a collection of hymns; there was likely to be a hymn of the same title but this has not been confirmed. The phrase is a symbol for and an implied metaphor for death: going into the silent land is going into the land of death. The probability is high that Rossetti would have known this collection (and the possible hymn). Even though she was born in 1830 and it was compiled in 1597, there is a strong likelihood that she would have known it. There is a very strong probability that the phrase was then in common use as a Christian allusion for death. I say there is a strong probability that she knew the hymn collection because, even today, church congregations sing hymns from long-gone centuries. Here are a few titles, and the dates of their composition, of hymns that are still sung in churches today, indeed, hymns some here grew up singing:
"O Christ, Thou Lamb of God"From the German, 1528"Praise God, from Whom All Blessings Flow"by Thomas Ken, 1695"Oh, Bless the Lord, My Soul"by Isaac Watts, 1719"Oh, for a Thousand Tongues to Sing"by Charles Wesley, 1739
To make it more interesting, Henry Wadsworth Longfellow composed a hymn titled "Into the Silent Land" in 1840. While it is not possible at this remove to speculate on whether English Christina Rossetti might have encountered American Longfellow's hymn, the hymn does illustrate that the phrase was current in Christian vernacular from the 1500s through the 1800s, 300 years. More importantly, it illustrates clearly and without any ambiguity that Rossetti sets firmly in the first two lines the point of the poem as remember me in death. Some are tempted to argue that "into the silent night" symbolizes the breaking up of a love affair; they incorrectly understand the silent land as the silence of rejected love. One verse of Longfellow's hymn very clearly illustrates the metaphorically symbolic meaning of the Christian allusion "into the silent land," clearly equating the silent land with death:

O land! O land!For all the broken-hearted;The mildest herald by our fate allotted,Beckons, and with inverted torch doth stand,To lead us with a gentle hand Into the land of the departed,Into the silent land!(Longfellow 1840)

Line 4: "half turn to go"
If you understand that the poetic speaker is dangerously ill and forestalling the shock of her death by providing comfort and guidance for herself and her beloved, and if you understand "the silent land" as a symbolic location for death, then you can understand how she would think of being on the brink of death as a "half turn to go" to the silent land. This abridged paraphrase of what she is saying may help to illuminate this concept:
[paraphrase] When I am gone to death and you can no more hold my hand and I can no more half-way turn toward death (but must turn all the way and go into the silent land), remember me.
Line 4: "yet turning stay"
Remembering that the speaker is dangerously ill and that she has at least once been on the brink of death and half turned to go "into the silent land," you can understand that "yet turning stay" describes an unexpected recovery that allows her to turn again toward life and to stay with the living: "half turn to go yet turning stay." In the context of the meaning of the 4 lines, she is saying: When I am dead and you cannot hold my hand nor can I be nearly dead but recover again, remember me.
Line 9: "for a while"
"For a While" is significant here because it helps define her relationship with her listener and it helps define what she is expecting to happen. A very specific amount of time is signified by "for a while": a short time. In other words, she is anticipating and expecting those times when life will intrude into his mourning and distract him by the demands of living into forgetfulness. This is not the forgetfulness following a deliberate action, like breaking up a romance between people who are dubious about their reciprocal love. This is the momentary forgetfulness caused by the distractions of being alive. Acknowledging that he might "forget [her] for a while" is a testament to the compassion, mercy and devotion of her love for him; this defines their relationship as one of the most sincere love.
Line 11: "the darkness and corruption"
The "darkness and corruption" is something that has the capacity to "leave" something. But what is it? The theme of the sonnet is remembrance: "Remember me." The problem brought out in the volta of the sestet is forgetting for a while: "[should you] forget me for a while." The "darkness and corruption" leaving something represents the solution to the paradox of remembering yet forgetting.
In light of these elements, darkness and corruption cannot logically represent something related to the listener: his darkness and corruption in grief cannot solve a problem of his making. What textual clue do we have that indicates the meaning of "darkness and corruption"?
The speaker anticipates going "into the silent land" of death. A classic Biblical allusion likens death to corruption and the land of death to darkness. The logically consistent source of "darkness and corruption" is not the listener nor the listener's grief and loss, but rather the logically consistent source is "the silent land" of death, which, in taking her away, "Gone far away," leaves something behind. What is left behind?: "A vestige of the thoughts that once I had" is left, safe from the silence of death.
Line 12: "vestige of my thoughts"
This phrase is an original expression of a standard poetic convention. Spenser talks about the words he writes in sand; Shakespeare talks about the poems he writes. All talk about the immortality imbued in poetry that attaches to the writer, the recipient/listener, to the words themselves. Like Spenser's words in sand, Rossetti's "vestige of my thoughts" are her poems, the words of her poems. In answer to our last question, "What is left behind?": The darkness and corruption of death in the silent land takes her but leaves a vestige of her thoughts. What does this reference? The vestige of her thoughts are her poems. If the paradoxical condition of forgetting while remembering is the problem, then her poems that live on after her are the solution.
In a complexly connected series of thoughts in logical progression, the speaker tells her beloved listener that if he forgets, the darkness will leave untouched her poems so he mustn't grieve, she will always--in a second paradox--be remembered by her words (and their readers) even while he forgets. So he should smile, not be sad.
Meaning of Text Lines 9-14
It may be tempting after a hasty reading of "Remember" to interpret lines 9-12 as the argument of a young woman who is dubious and ambiguous about her love for her supposed beloved. It might be tempting to think she is acknowledging that his love for her is equally dubious and that he will all too soon conquer his grief and rebuild his life. It may be tempting to think that she has realized that she has never fully loved him, that she has had doubts throughout their time together. But if you know that a sonnet presents a point of argument and a counterpoint and that the counterpoint presents a problem and a solution and that the solution represents a paradox, then you will realize that this hasty sort of interpretation is in conflict with the text and fails to reflect the form and meaning of the text.
What is the meaning of the text in lines 9 through 12?

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

The speaker has just reminded her beloved, in lines 1-8, that when she is gone into the silent land of death, he will no longer hold her hand; he will no longer plan or speak of their future life together (seemingly her illness has prevented them from marrying); he will no longer be able to comfort and counsel her and pray for her. Her request of him is that, with all this that they will lose, he remember her: "Remember me when I am gone ... / far away into the silent land." The theme is being remembered after death. The point being argued is that, when she is so ill that she must turn to go toward death when she can no longer recover, he must replace the planning and counsel and prayer--which will do no good then--with remembrance of her.
The counterpoint being argued from the line 9 volta to line 12, is that while life may distract and cause him to forget for a while--"for a while" is critical to understanding the depth of their love, the dynamic of their relationship and the problem presented--the "darkness and corruption" of death will not touch the vestige of her thoughts as expressed in her poems.
This is a sonnet of mourning written by a poetess, not automatically assumed to be the poet herself (the poetic speaker is not always the poet), whose words will live as a "vestige" of her thoughts after she has died. This is a standard Shakespearean convention that was used equally by Edmund Spenser: the poet's words bestow immortality. Rossetti has given the convention a new aspect and says that her words will remember her. This remembrance clarifies the problem of the sonnet and the solution.
The problem is that humans cannot always remember the beloved departed: they forget even in mourning. The solution is that her poems will keep her immortal by remembering her to the world through their substance: "A vestige of the thoughts that once I had" refers to her poems. The first four lines, 9-12, of the sestet and are her way of comforting her beloved when explains why he need not grieve for forgetting for a while: her words also remember her to the world, to all who read them.
Anyone who has grieved over the death of a loved one knows there are moments in their days during which the world intrudes and forces distraction from grief through the demands of productivity or admits distraction through unexpected laughter with a child or a playful kitten. For the grieving mourner, these moments of distracted living amplify grief and add new grief over the moments we forgot. The poetic speaker recognizes this new grief by acknowledging the inevitability of forgetting and by forestalling grief through compassion and forgiveness and by presenting her original understanding of a poet's immortality: the words hold the remembrance.
What is the paradox of the resolution?
An element of sonnet form is the paradox in the resolution. A paradox is something that seems false but is nonetheless true. Rossetti, who is recognized as the master of form among her generation of poets in Victorian England, has given us two paradoxes. The first paradox is between the octave--in a rhyme scheme of abbaabba--and the sestet--in a rhyme scheme of cddece (the rhyme scheme is central to building the flow of logic in a sonnet). The paradox is: remember me while you forget. The second paradox is in the resolution and is represented by the conflict between "forget" and "smile." Forgetting would be to fail to honor her request, her love and his own love, yet she advices him that it is better to "forget and smile" while discouraging remembering and being sad. It seems false, yet it is true because her poems eternally keep her remembrance offered to those readers who read the vestiges of her thoughts in them.