Ophelia here seems to have lost her mind following her father's burial ("to think they should lay him i' the cold ground"). She talks in riddles and sings songs about love and death. Hamlet, IV.vQueen Gertrude:
Alas, look here, my lord.
[Sings] Larded with sweet flowers
Which bewept to the grave did go
With true-love showers.
How do you, pretty lady?
Well, God 'ild you! They say the owl was a baker's
daughter. Lord, we know what we are, but know not
what we may be. God be at your table!
Conceit upon her father.
Pray you, let's have no words of this; but when they
ask you what it means, say you this:Sings
To-morrow is Saint Valentine's day,
All in the morning betime,
And I a maid at your window,
To be your Valentine.
Then up he rose, and donn'd his clothes,
And dupp'd the chamber-door;
Let in the maid, that out a maid
Never departed more.
Indeed, la, without an oath, I'll make an end on't:Sings
By Gis and by Saint Charity,
Alack, and fie for shame!
Young men will do't, if they come to't;
By cock, they are to blame.
Quoth she, before you tumbled me,
You promised me to wed.
So would I ha' done, by yonder sun,
An thou hadst not come to my bed.
How long hath she been thus?
I hope all will be well. We must be patient: but I
cannot choose but weep, to think they should lay him
i' the cold ground. My brother shall know of it:
and so I thank you for your good counsel. Come, my
coach! Good night, ladies; good night, sweet ladies;
good night, good night.