What happens to the relationship between Modou and his first wife, the narrator? Do you think it is Binetou's fault for how Modou handles his two marriages?

Modou does not follow the Muslim polygamic rules-instead of sharing his time between his two wives, he avoids the narrator. In spite of the advice of friends and family, he ends up abandoning his first family altogether. Somebody said that it was Binetou's fault, but Modou is a middle-aged male in a country where males are more valued than females, so it is likely that Binetou, being a girl barely out of her teens would pressure her new husband.Therefore, it is likely Modou makes the choice himself to avoid his first wife as he does not have the courage to look her in the eye.