What incidents in the novel reveal that Leonce may not be a good husband for Edna?
Very early in the novel, when Leonce returns home late from his club, he wakes Edna up with his noise and chatter. Despite her being fast asleep, he is discouraged "that his wife, who was the sole object of his existence, evinced so little interest in things which concerned him and valued so little his conversation." I repeat: she'd been quite asleep when he arrived, and it was his rudeness that awakened her.
In order to compel her to get up, it seems, he then seemingly makes up a story about their son, Raoul, being sick. When Edna reassures him that the boy is fine, "he reproached his wife with her inattention, her habitual neglect of the children. If it was not a mother's place to look after children, whose on earth was it? . . . He talked in a monotonous, insistent way," as though it is habit for him to lecture her like this. This led to tears and the beginning of Edna's recognition of "an indescribable oppression, which . . . filled her whole being with a vague anguish." This is certainly not the way good husbands make their wives feel. If Leonce is unhappy with his wife's lack of attention to him or their children, there are certainly more constructive and less passive-aggressive ways to draw her attention to it. If he wanted a "mother-woman," then he ought to have married one.
Later, after the first night on which Edna swims out by herself into the ocean, Leonce gets irritated with Edna that she isn't feeling, or at least pretending to feel, amorous. He orders her to come inside, but she refuses.
She heard him moving about the room; every sound indicating impatience and irritation. Another time she would have gone in at his request. She would, through habit, have yielded to his desire; not with any sense of submission or obedience to his compelling wishes, but unthinkingly, as we walk, move, sit, stand, go through the daily treadmill of the life which has been portioned out to us.
Continuing to ignore her own feelings and her desire to remain outside on a lovely night, he then calls "fondly, with a note of entreaty," apparently unwilling to accept or believe that she would refuse him when she, evidently, never has before. However,
She perceived that her will had blazed up, stubborn and resistant. She could not at that moment have done other than denied and resisted. She wondered if her husband had ever spoken to her like that before, and if she had submitted to his command. Of course she had; she remembered that she had.
Certainly, a good husband would not become petulant and childish when his wife doesn't obey his every command, and nor would he wish her to ignore her own feelings only to gratify his. Edna needs a husband who can respect her will, and Leonce does not. They are not a good match.
Leonces's flaw as a husband is the result of his belief in the traditional roles of Acadian society and of his unwillingness and inability to communicate effectively with Edna.
As a "traditional" Creole gentleman of the times, Leonce believes it is his duty to provide financially for the family and it is Edna's duty to be devoted to him, their two children, and their home. When Edna suggests she is not interested in these domestic duties, Leonce is almost incapable of comprehending what she means. In his mind, this line of thinking is utterly ridiculous. In short, Leonce does not think of Edna as an equal partner in marriage or in life, he thinks of her merely as another member of his employ.
Against that backdrop, Leonce's inability to communicate effectively with his wife exacerbates the problem. When Edna shares her feelings with Leonce, he dismisses them. When her behavior contradicts his expectations, he dismisses them as well, choosing to believe that it is simply a phase through which Edna will pass. By dismissing Edna and her concerns and never communicating with her about them, Leonce severs any ties that exist between the two.