Behaving badly
Often when we have grown up and we have a bit of distance from the circumstances of our childhood, we can see our behaviors for what they were. In this case, the woman has realized that her emotional trauma around her parents’ divorce made her act horribly toward her stepmom.
I find it a little unfair that her stepmom is cross with her statement about being a newlywed. Surely, as an adult, she could look at the behavior of the child and understand what was going on behind it. Holding a grudge against someone for this long isn’t healthy.