The answer depends on how the other will respond. If that person is not ready to hear those words or to seek forgiveness, then rejection of your overture can happen. If the other sees no wrong in the actions, then rejection of your overture again can happen. In other words, it depends on the circumstances between the two of you. You certainly can say within yourself to the other, “I forgive you, “ and this is reasonable if proclaiming those words to the other will create more tension between the two of you.
For additional information, see 8 Keys to Forgiveness.