You tackled a sensitive subject here and you managed surprisingly well to show it from the perspective of a child.

It's always hard for a little kid to understand why parents fight or the family breaks apart and it has to "choose" between the parent it wants to stay at. Children are self-centered, they don't understand that not everything good or bad going on around them is about themselves; they only learn to distinguish with time and learning more about the world around them. That isn't meant as offense, it's a psychological fact.

It's also a fact that children try to rationalize what they can't understand: the facts of their parents fighting and separating and divorcing by either blaming themselves as the reason for it and later the parents for forcing the bad feelings the first caused on them.

The result is they lash out at the parents/stepfamilies in helpless anger, "hate" them, become mentally ill or disturbed (it's a heavy emotional burden to apparently be the reason for the family breaking apart) and the adults often don't notice it: either they misinterpret the signs the child sends and/or are caught up too much in their own confused feelings to see it what strains the connection between parents and children even more.

It's a long and rocky way to work things out and the hardest step is to see what everyone did to everyone else with not seeing the pain they caused each other, apologizing or at least acknowledging it. It's a long way of realization, reapproximation and forgiving the family in this story (yours?) went and as it looks it worked well. But it also shows that Happy Endings don't rain down from heaven, but one has to work hard for one's and his/her family's happiness.