Being a loving step-parent can be incredibly complicated when you're dealing with a child who holds onto unfounded resentment through adulthood. While we've all heard and seen the evil step-mother tropes in Disney movies and beyond, most realities are far more complicated, and there are certainly situations where step-children lash out and hurl their pain at an innocent step-parent for daring to fall in love with their mom or dad.
Finding ways to navigate a one-sided relationship with a step-child can be near impossible, particularly when they've grown into bitter adults who never considered your perspective. This difficulty is compounded by the desire to please your partner, and consider the importance of their relationship with their child.
AITA for not being able to forgive my stepson and banning him from our home?
She was not dating the step-son's father during the dissolution of the marriage, and there was no foul-play on OP's end at all. She just happened to fall in love with a divorced dad.