I think it is easier to forgive than forget. Because forgiving is something you do for yourself. When you forgive you no longer hold on to the anger and the bitterness and then it is easier to allow the memories to drift further and further into the past. Forgiving does not mean you have to go over to that person and tell them you forgive them, nor does it mean you have to have a relationship with them from that moment on. It means that in your heart you choose to forgive them and not hold on to the grudge, the bitterness and the anger any longer. If and when you see that person in the street you will no longer stare daggers at them or feel the need to spit at them, you will choose to pass them by as if you do not know who they are. Or if it is someone closer to you, in time you might choose to build a new relationship step by step.
It is a matter of taking control back. You did not have control over what happened to you and the choice the other person made when they hurt you. However, you do have control over the choices you make today. YOU have the choice if you wish to stay angry and use your energies on that and you have control on whether you wish to choose to work on releasing that anger and using your energies on something more productive and enjoyable in your life. It is in YOUR control and it is YOUR choice how you wish to deal with each and every issue in your life.