I shared this thought on Facebook a few months ago.
The truth is..
...that the other person isn't affected very much by our unforgiveness. We can punish them with our silence or other ways, but we are limiting our fellowship with God. They may be seeing the difficulty in the relationship as an opportunity to grow stronger in faith while we are growing weaker. Their testimony will grow louder while ours stops speaking. They will be basking in His glory while we wallow in the filth of our rebellion against God's way of doing things. We will blame them for our misery, but our unforgiveness is self bondage. Choose this day whom you will serve.