Need help with plot? CONFUSED?

In my story, the main character is seen as responsible for the disappearance of her fiance's kid sister. The child is later found dead. Is it reasonable for the mother of this child to hold it against my main character and not want to forgive her although she is consciously aware that what happened to her daughter was unintentional. A horrible mistake. Should the main character expect forgiveness from the mother at one point? Is the mother justified in hating her? Which would you rather happen? Forgiveness or no forgiveness? Thanks. Your help is greatly appreciated.