If one curses his father or his mother,
his lamp will be put out in utter darkness.
Should this proverb be interpreted to mean if a child curses his good father or mother? Certainly the Scriptures instruct fathers and mothers to be good, and the premise in Proverbs is that fathers and mothers have wisdom that their children should heed. Even so, it is the specific family bond that is stressed. It is wrong to curse anyone, but to send curses in the way of one's parents is especially appalling. Indeed, it is regarded here as sacrilege.
The special nature of bond between parent and child is recognized by everyone. The reason there is much dysfunction in families is because offense between parent and child (particularly parent against child) carries more significant impact. Scripture understands this; Scripture teaches it should be so. A parent is not a mere provider for the child until he reaches adulthood. "Father," "Mother," carries with that name a profound bond.
So what is your regard for your father and mother, be they living or dead? Whoever you are reading this, you have your own context in thinking about this. You may have had a wonderful relationship with your parents or a terrible one. Even so, it is vital that you recognize the peculiar relationship of a parent to a child. You may know others who are like a father or mother to you; others who may legally have taken that role. You should of course show them due deference. But if you struggle about your feelings towards your biological parents, even so, do not fall into the sin of cursing them. You do not have to excuse their sin or deny their offense. You do not have to conjure up loving feelings. But still, for your own sake, do not fall into the pit of bitterness that leaves you desiring judgment to fall upon your parents. They must answer to their own sins before God. Your curses are not needed for them to get their due. But your prayers are needed for the hope of the Spirit's work in their hearts.
Is this not what the gospel is about - bringing hope to those who do not deserve it? It was for his crucifiers that Jesus asked his Father for forgiveness. It was for his enemies that God sent his Son to die. If the gospel has penetrated your heart, then forgiveness (not curses) is what will come forth. You cannot change your parents; you cannot create new feelings; but you can offer the blessing and forgiveness in Christ to your parents that have been given to you.