I cannot even think of forgiving the person. I don't want to resolve my relationship.
Forgiveness is more about yourself than about the other person. The intent is to let go of the burden from your heart. We often feel, forgiveness is about the other person. But, it is 100% about us, as you are the one who is carrying the weight.
Also, forgiveness does not mean that you have to continue the relationship with that person. It simply means to set ourselves free from the emotions that we are carrying deep within. However, if you are not ready for it, or you don't feel like forgiving the person, don't do it. It won't help in any way.
You can become aware, of how holding on to unpleasant emotions is affecting you. Slowly with time, you'll feel the need to let it go. Give yourself that time.