It can be difficult to forgive someone you love after they have truly hurt you. Some people are able to move past it and have a fresh start. For others, the anger, bitterness and resentment remains. To forgive, but not forget is something that you may have said, or have heard others say. But it is this frame of mind which imprisons you both, where neither will ever be free.
If you were interested in reading more about forgiveness, Psychologist Dr David Wells has written a helpful article here.