Final answer:
The protagonist is showing an internal conflict, an emotional or moral struggle, often highlighted in literature such as Shakespeare's Hamlet where familial relationships can cause significant psychological turmoil.
Step-by-step explanation:
If the protagonist of a fictional story constantly agonizes about his relationship with his mother, he is expressing an internal conflict. This type of conflict takes place within an individual and can involve a struggle with emotions, morals, or personal dilemmas. Literature often explores such internal conflicts deeply, particularly when characters are faced with complex relationships or intense emotions. Works like Shakespeare's Hamlet exemplify this, where Hamlet's profound emotional turmoil regarding his mother's actions forms a central theme of the play. Similar to Hamlet, other characters in literature may experience immense psychological struggles resulting from familial relationships, which can become a dominant force in their lives and narratives.