Wikipedia says:
Gertrude is first seen in Act 1 Scene
2 as she tries to cheer Hamlet over the loss of his father,
begging him to stay at home rather than going back to school
in
Wittenburg.
Her worry over him continues into the second act, as she
sides with
King Claudius
in sending
Rosencrantz and Guildenstern
to raise the spirits of her son. Also, rather than ascribing
Hamlet's sudden madness to Ophelia's rejection (as thought
by Polonius), she believes the cause to be his father,
King Hamlet's
death and her quick, subsequent marriage to Claudius: "I
doubt it is no other but the main; His father's death and
our o'erhasty marriage."[1]
In Act three, she eagerly listens to the report of
Rosencrantz and Guildenstern on their attempt to cheer him,
and supports the King and Polonius' plan to watch Hamlet
from a hidden vantage point as he speaks with Ophelia, with
the hope that her presence will heal him.
In the next act,
Gertrude tells Claudius of Hamlet's murder, convinced that
he is truly mad. She also shows genuine compassion and
affection as she watches along with others as Ophelia sings
and acts in absolute madness. At Ophelia's burial, she
expresses her former hope that the young woman might have
married her son: "I hoped thou shouldst have been my
Hamlet's wife."[2]
When Hamlet appears and grapples with Laertes, she asks him
to stop and for someone to hold him back—saying that he may
be in a fit of madness now, but that will alleviate soon.
In the final scene,
Gertrude notices Hamlet is tired during the fight with
Laertes, and offers to wipe his brow. She drinks a cup of
poison intended for Hamlet by the King, against the King's
wishes, and dies, shouting in agony as she falls: "No, no,
the drink, --O my dear Hamlet,-- The drink, the drink! I am
poison'd."[3]
Other characters' views of the Queen are
largely negative. When the Ghost of her former husband
appears to Hamlet, he describes her as a "seeming virtuous
queen," but orders Hamlet not to confront her about it and
leave her judgement to heaven. However, he also expresses
that his love for her was benevolent as he states that he
would have held back the elements if they "visited her face
too roughly."
Hamlet sees her as an example of the
weakness of women (which affects his relationship with
Ophelia) and constantly hurt in his reflections of how
quickly (around two months) she remarried.
Sparknotes
writes:
Few Shakespearean characters have caused as much
uncertainty as
Gertrude, the beautiful Queen of Denmark. The
play seems to raise more questions about Gertrude
than it answers, including: Was she involved with
Claudius before the death of her husband? Did
she love her husband? Did she know about Claudius’s
plan to commit the murder? Did she love Claudius, or
did she marry him simply to keep her high station in
Denmark? Does she believe
Hamlet when he insists that he is not mad, or
does she pretend to believe him simply to protect
herself? Does she intentionally betray Hamlet to
Claudius, or does she believe that she is protecting
her son’s secret?
These questions can be answered in numerous ways,
depending upon one’s reading of the play. The
Gertrude who does emerge clearly in
Hamlet is a
woman defined by her desire for station and
affection, as well as by her tendency to use men to
fulfill her instinct for self-preservation—which, of
course, makes her extremely dependent upon the men
in her life. Hamlet’s most famous comment about
Gertrude is his furious condemnation of women in
general: “Frailty, thy name is woman!” (I.ii.146).
This comment is as much indicative of Hamlet’s
agonized state of mind as of anything else, but to a
great extent Gertrude does seem morally frail. She
never exhibits the ability to think critically about
her situation, but seems merely to move
instinctively toward seemingly safe choices, as when
she immediately runs to Claudius after her
confrontation with Hamlet. She is at her best in
social situations (I.ii and V.ii), when her natural
grace and charm seem to indicate a rich, rounded
personality. At times it seems that her grace and
charm are her only
characteristics, and her reliance on men appears to
be her sole way of capitalizing on her abilities.
Hamlet's mother and the foolish, weak-willed
Queen of Denmark. She is accidentally killed in the finale by
drinking poisoned
wine that Claudius intended for Hamlet.