Forgiveness is hard. Especially in a marriage tense with past troubles, tormented by fears of rejection and humiliation, and torn by suspicion and distrust. Forgiveness hurts. Especially when it must be extended to a husband or wife who doesn't deserve it, who hasn't earned it, who may misuse it. It hurts to forgive. Forgiveness costs. Especially in marriage when it means accepting instead of demanding repayment for the wrong d…