Character A was abused, mistreated, neglected, or simply treated poorly in the past by an ex or a family member. (Normally Character A in this scenario is the female half of a m/f relationship, or the adult child of a parent — usually a father — who did something ranging from abuse to bad parenting to cause the adult child to be extranged from their parent.) The ex-partner or estranged family member shows back up in Character A's life, Character A reacts with hostility ... and all the other characters on the TV show/in the film start pressuring them to forgive their ex or family member, to stop being so bitter, to show forgiveness, for the sake of 'healing' and 'closure' etc etc. By the end of the film, or the TV episode, Character A has forgiven this person, and patched up the relationship.

Oh good lord yes, this. Although I basically avoid storyline like that these days, because no. It doesn't make me react like other things do, but I simply don't go for this, also definitely due to personal baggage. I do not condone this sort of thing irl though, I've had at least one situation where I needed to sit someone (a colleague) down and tell them why making such comments or asking specific question might be a Really Bad Idea.