What does Shakespeare's couplet (to love that well, which thou must leave ere long) mean to you?

By William Shakespeare

Like as the waves make towards the pebbled shore,
So do our minutes hasten to their end;
Each changing place with that which goes before,
In sequent toil all forwards do contend.
Nativity, once in the main of light,
Crawls to maturity, wherewith being crown'd,
Crooked eclipses 'gainst his glory fight,
And Time that gave doth now his gift confound.
Time doth transfix the flourish set on youth
And delves the parallels in beauty's brow,
Feeds on the rarities of nature's truth,
And nothing stands but for his scythe to mow:
And yet to times in hope my verse shall stand,
Praising thy worth, despite his cruel hand.

Shall I compare thee to a summer's day?

Thou art more lovely and more temperate.

Rough winds do shake the darling buds of May,

And summer's lease hath all too short a date.

Sometime too hot the eye of heaven shines,

And often is his gold complexion dimmed;

And every fair from fair sometime declines,

By chance, or nature's changing course, untrimmed;

But thy eternal summer shall not fade,

Nor lose possession of that fair thou ow'st,

Nor shall death brag thou wand'rest in his shade,

When in eternal lines to Time thou grow'st.

So long as men can breathe, or eyes can see,

So long lives this, and this gives life to thee.



That time of year thou mayst in me behold

When yellow leaves, or none, or few, do hang

Upon those boughs which shake against the cold,

Bare ruined choirs, where late the sweet birds sang.

In me thou see'st the twilight of such day

As after sunset fadeth in the west;

Which by and by black night doth take away,

Death's second self, that seals up all in rest.

In me thou see'st the glowing of such fire,

That on the ashes of his youth doth lie,

As the deathbed whereon it must expire,

Consumed with that which it was nourished by.

This thou perceiv'st, which makes thy love more strong,

To love that well which thou must leave ere long.