Is a person sinful for hating those who have wronged him, especially if this hatred is a result of repeated and severe mistreatment?

A mere aversion of the soul and its dislike for someone who wronged it, without malice or hatred, carries no fault. This is because the heart's reactions are instincts over which a person has no control, and thus are not subject to divine injunctions. Allah has created hearts to dislike those who wrong them and to love those who treat them well.

However, one should not surrender to this innate dislike to the extent that it leads a person to desire evil for others, or to harbor resentment and malice towards them. One should rather forgive missteps and pardon, for what is with Allah is better and more enduring.