Gertrude is not the only sexualized woman in Hamlet. Hamlet speaks to Ophelia in explicitly sexual terms, particularly in act 3, scene 2, as they are about to watch the play. However, it is true that Hamlet speaks to his mother in a strange and disturbing manner, more like an overbearing father than a son. This is typical of the way in which Gertrude is represented as a passive character and an empty vessel. She is Hamlet's mother, King Hamlet's widow, and Claudius's wife, but never an agent in her own right.
The actress who plays Gertrude is given an unusual amount of latitude, even by the standards of Shakespeare's women, to create the character. It is equally plausible to play her as an innocent victim with no particular desires of her own, or as Claudius's willing accomplice. Gertrude's position at the end of act 3, scene 4 is particularly ambivalent. It is reasonable to assume that she is frightened of her son, who has been behaving madly, talking to the ghost (an apparition which remains invisible to her), and has just killed Polonius, a matter which seems to concern him very little.
Although Gertrude says earlier in this scene that Hamlet's words have turned her eyes into her soul, it is not clear that they have any lasting effect on her. By the end of the scene, she may well be saying whatever she thinks necessary to placate him. Gertrude lives and dies a mystery, upon whom actresses, directors, audiences and readers can project a myriad of personalities, just as those around her do within the play.