There is an interesting discussion of the concept of Sehnsucht at http://en.wikipedia.org/wiki/Sehnsucht#In_psychology where it rather neatly states from Scheibe, S.; Freund, A. M., & Baltes, P. B. (2007). “Toward a developmental psychology of Sehnsucht (life longings): The optimal (utopian) life”.Developmental Psychology (43): 778–795;(Psychologists have worked to capture the essence of Sehnsucht by identifying its six core characteristics: “(a) utopian conceptions of ideal development; (b) sense of incompleteness and imperfection of life; (c) conjoint time focus on the past, present, and future; (d) ambivalent (bittersweet) emotions; (e) reflection and evaluation of one’s life; and (f) symbolic richness.”

Woman
It is not quite nostalgia but clearly a term that can be associated with Romanticism. The above link makes clear that, ” Sehnsucht is a compound word, originating from an ardent longing or yearning (das Sehnen) and addiction (die Sucht)”. Hence, Schiller writes:-
O zarte Sehnsucht, süßes Hoffen,
Der ersten Liebe goldne Zeit!
Das Auge sieht den Himmel offen,
Es schwelgt das Herz in Seligkeit.
O dass sie ewig grünen bliebe,
Die schöne Zeit der jungen Liebe.
( O tender yearning, sweet hope,
the first love golden time!
The eye sees the heavens open,
it revels in the heart of bliss.
O that they would remain ever green,
The beautiful time of young love.)

Knowing
Indeed, zarte is another lovely word indicating great tenderness. Collins large dictionary gives this example- der dritte Satz hat etwas Sehnsüchtiges – the third movement has a strangely yearning quality.
Here is Hartmann’s Poem-
Und kommst du nicht am Tage
Und kommst du nicht am Tage,
So komm im Traum zu mir;
Gewiß, gewiß ich sage
Dir tausend Dank dafür.
Komm immer so wie heute,
Da ich entschlummert kaum,
Wie holdes Brautgeläute
Erklang mein ganzer Traum.
Wohl sind noch meine Lider,
Wenn ich erwache, feucht –
Doch komme immer wieder,
Vor Glück weint’ ich vielleicht.
Ich fleh’ es, wie mit Kosen
Der Nachtigall Gebet
Vom jungen Frühling Rosen
In kalter Nacht erfleht.
O komm mit aller Plage,
Die du mir schon gebracht,
Und kommst du nicht am Tage,
So komm im Traum der Nacht.
Hartmann (1821 – 1872), was an Austrian writer and a radical politician, member of the Frankfurt National Assembly, wrote among other things, “Chalice and Sword”-»Kelch und Schwert« More information may be found at http://de.wikisource.org/wiki/BLK%C3%96:Hartmann,_Moriz

In the Clear
Don’t come in daytime
Don’t come in daytime
but come to me in my dreams.
Confidently, certainly, gladly
I thank you again one thousand times
Always come like you did today,
since I can scarcely slumber.
Lovely wedding bell chimes echo
through all my dreams
Even my eyelids are refreshed
when I awake with tears.
Always come back again
blissfully crying, “I might”.
I beg you with a tender caress
like the nightingale’s plaintive song
amidst young spring roses
yearning into the chill of the night.
Come again with all the trouble you have already brought
But don’t come by daytime
But come in dreams by night!
As usual there is much to learn from Goethe, particularly at -http://en.wikipedia.org/wiki/Nur_wer_die_Sehnsucht_kennt and perhaps another time is needed to tease out the meanings of Leidenschaft but here is as good a start as any :-http://synonyme.woxikon.de/synonyme/leidenschaft.php

Forgetting
There is a great exhibition of Janet Lynch’s beautiful paintings from Cornwall Contemporary at the moment and they go rather well I hope with the poem. Please see http://www.cornwallcontemporary.com/JanetLynch_JaneMuir53.html