Final answer:
Hamlet's insistence that Gertrude abstain from relations with Claudius primarily concerns the betrayal of his father's memory. His disgust and distress revolve around a sense of degradation related to his mother's actions, which fuel his emotional conflict in the narrative.
Step-by-step explanation:
When Hamlet insists that Gertrude abstain from having sexual relations with Claudius, his primary concern is the betrayal of his father's memory. Hamlet's intense emotions toward his mother are a central theme in the play, and his disgust and anger about Gertrude's relationship with Claudius stem from a deep sense of betrayal and a complex psychological conflict. This conflict is not just about moral implications, the potential harm to Gertrude's reputation, or even the direct threat Claudius poses to their family, but about the overarching emotional impact of his mother's actions on his perception of his deceased father.
Indeed, Hamlet's relationship with his mother and his reaction to her marriage to his uncle after his father's death are considered by many scholars to be the core issue of the play. Hamlet is depicted as being obsessed with his mother's supposed degradation and is unable to separate his personal anguish from the act of revenge he contemplates against Claudius. In examining the ghost's role, intentions, and the critical interpretations of Hamlet's actions, the play engages deeply with the psychological and emotional turmoil that Hamlet navigates throughout the narrative.