David's problems have now become full-grown. We can draw a direct line from his callousness to Bathsheba and Uriah to the revolt of his son Absalom and the prince's death.
We first meet Absalom when his sister, Tamar, is assaulted by their half-brother, David's eldest son Amnon. Although the crime warrants punishment under the law, David loves Amnon and takes no action against him. Nor does he do anything to redeem Tamar's honor. So Absalom waits two years and invites all the king's sons, including Amnon, to a feast, then sends servants to murder Amnon and avenge his sister. He himself is exiled three years for this crime, and returns with an understandable load of bitterness towards David.
For four years, Absalom builds support among the people and then makes a lightning bid for the throne. David, caught unaware, has to flee with his court in order to save his life, but he leaves spies. Absalom sleeps with his father's concubines in order to promote to the people that he is the king now, rather than David.
But David's spies have allowed David the time to gather an army of his own and attack. They rout Absalom's army, which is not prepared because the spies have fed him false information. Absalom himself is somehow caught in a tree, helpless, where he is later killed by the general Joab, David's nephew. On hearing this, David falls to the ground, weeping and saying he would rather have died himself instead of Absalom dying.
You may remember that when Saul was trying to kill David, David would only flee from Saul and wouldn't attack him. Even though he had two chances to kill Saul, he refused to strike someone the Lord had anointed to be king. David recognized that God chose the kings of Israel, and he had no right to take from Saul what God had given to him.
But Absalom has no such scruples. Had David not fled, we can little doubt that Absalom would have had him killed in order to solidify his claim to the throne. He has no respect for the Lord's anointed. In fact, we don't really see him pay much attention to the Lord at all. Especially during his time of exile, David prays to God all the time. He doesn't always keep God in mind later on during his reign, but his contact with God and his seeking God's direction are still frequent.
Absalom, on the other hand, takes every action on his own. His justifiable rage against Amnon and his disgust with the fact that David does nothing turns into his plot to take justice by his own hand. He will not wait for time to bring him his chance at the throne if that's the will of God, but tries to grab it for himself. He doesn't seek advice from the priests or from prophets, but from court advisers who see things only in political terms. God may have chosen the first two kings of Israel, but the third king will choose himself, thank you very much. He'll play by his own rules.
That last habit, I imagine, he learned by watching his father. David played by his own rules when he wanted Bathsheba. He played by his own rules and ignored God's law when he "solved" his problem with Uriah's murder. He created a culture of the idea that being powerful meant you didn't have to follow the same rules everyone else did. So Amnon didn't, and he died. And then Absalom didn't, and he died.
Had either young man come back to his father and said, as did the younger son in the story of the prodigal, "Father, I have sinned against heaven and against you and am no longer worthy to be called your son," what would have happened? We can't know, but my guess is that something of the peace of the house might have been restored. But such actions would require real repentance, a real turning around to a new way of living, and neither of them could do that.
If we live life by our own rules and guide our actions according to whatever we want, we bring discord and maybe even destruction wherever we go. Only by living life according to God's law of love and respect for others and for God himself can we live lives that match what our spirits were created for, and thus find the peace we can't get otherwise.
The good news is that we have a chance to do that every time we fail. Thanks be to God.