Ken Sande, The Peacemaker : A Biblical Guide to Resolving Personal Conflict, Baker Books, 3d ed., 2004, p. 252.
Do all you can to be reconciled to others, but remember that you cannot force others to do what is right. If you have done everything within your power to resolve a conflict, you have fulfilled your responsibility to God and may stop actively trying to solve the problem (Rom. 12:18)… It is not necessary or wise to waste time, energy, and resources fretting about someone who stubbornly refuses to be reconciled.
Ken Sande, The Peacemaker: A Biblical Guide to Resolving Personal Conflict, Baker Books, 3d ed., 2004, p. 252.