Forgiveness is vital to your Christian walk. You cannot progress spiritually until you forgive. Your sacrifices an offerings are not acceptable until you forgive.
Therefore if thou bring thy gift to the altar, and there rememberest that thy brother hath ought against thee;
Leave there thy gift before the altar, and go thy way; first be reconciled to thy brother, and then come and offer thy gift. Matt. 5:23 - 24
What is more, you have to love your enemies. You have to greet them. Now I always thought of this as people who are catty with you, or like mean girls or whatever, but the enemies indicated by the original Greek are blood enemies... People who seek to kill you. Greet doesn't mean just a nod from across the street either. It means walk with, visit, and hang out with these people. This sounds crazy till we look at the life of Christ. Jesus was always available to the Pharisees and Scribes who eventually had him crucified. Jesus did visit them in their homes. Now this is dangerous stuff. Jesus got crucified doing this, and I suspect it plays a role in taking up our own cross and following him.
We do have to forgive completely and fully and find love in our hearts for the people who hurt us, as well as those who are nice to us. That is what sets us apart as Christians. Now this kind of love can come only from God. God loves us and forgives us, therefore we must forgive others. WE have all hurt God, we've hurt our earthly parents in the same way as they watched us fail, fall into sin, lie to them and etc. We have hurt God and others who care about us. We want to be forgiven, and so we absolutely must forgive. God helps us by pouring out his perfect love upon us, and from that we must overflow with love for others in return. Love and Forgiveness go hand in hand, and without love, well we can't be Christians without love and forgiveness. These are the keystone of Christianity. For more information on how this works, check out my book,
http://www.amazon.com/Jesus-Help-need-Miracle-Spiritual/dp/150108464X