What means this scene of rude impatience?

Duchess
What means this scene of rude impatience?
Queen Elizabeth
To make an act of tragic violence.
Edward, my lord, thy son, our king, is dead.
Why grow the branches when the root is gone?
Why wither not the leaves that want their sap?
If you will live, lament. If die, be brief,
That our swift-wingèd souls may catch the King’s,
Or, like obedient subjects, follow him
To his new kingdom of ne’er-changing night.

Edward, my lord, thy son, our king, is dead.
Why grow the branches when the root is gone?
Why wither not the leaves that want their sap?

Duchess
Ah, so much interest have I in thy sorrow
As I had title in thy noble husband.
I have bewept a worthy husband’s death
And lived with looking on his images;
But now two mirrors of his princely semblance
Are cracked in pieces by malignant death,
And I, for comfort, have but one false glass
That grieves me when I see my shame in him.
Thou art a widow, yet thou art a mother,
And hast the comfort of thy children left,
But death hath snatched my husband from mine arms
And plucked two crutches from my feeble hands,
Clarence and Edward. O, what cause have I,
Thine being but a moiety of my moan,
To overgo thy woes and drown thy cries!