Sadly, not all parents or grandparents are honorable people. Properly respecting those whose behavior is less than honorable is not easy. For instance, victims of persistent verbal, physical or sexual abuse usually find it difficult to honor the guilty parent. God does not demand, in the Fifth Commandment, that children of such parents continue to subject themselves or their children to mistreatment.
Still, we must honor our forebears. How can we honor parents or grandparents whose behavior is unworthy of admiration? How can we apply this commandment to them?
First we must deal with our own attitudes. Jesus tells us to love and pray for even our enemies (Matthew 5:44-45). This applies to parents who have mistreated us or whose example we cannot respect. We should harbor no hate or malice toward them. We may strongly disapprove of their way of life. We may disdain their sinful behavior. But we must not despise them as persons. That is where God has drawn the line for us, and we are blessed when we stay on the right side of the line.
Next, when we have occasion to converse with or about our parents or grandparents, we should refrain from derogatory remarks and treat them with courtesy and respect. We should pray that God will help them understand the error of their ways so they can be reconciled to Him and through Him eventually with us.
Finally, we should conduct our lives in a way that honors them through the example we set as their sons and daughters. Our own proper behavior can bring them honor they have never personally earned.