When someone does me wrong, I usually have no problem forgiving them because I don't like carry grudges if only makes me feel bad and really does nothing to help the situation. If someone never ask for forgiveness I almost always tell them that I for give them and let them know I only give them one chance and if they do it again they are no longer my friend or in my life. No some people like relatives and family friends you have to deal with them no matter what.
One thing to always remember any time you forgive someone don't forget what they did. If you forget what they did to you then you will never forgive yourself for letting them do it again and they will if you forget. So remember it OK to forgive but its not OK to forget.