Complex sentence: Because of this, the king's physician advised the king that there should be no more children; therefore, the king stopped visiting his wife's bedroom and spent all his time with his longtime mistress, Diane de Poitiers.
Split into simpler sentences: Because of this, the king's physician advised the king that there should be no more children; therefore, the king stopped visiting his wife's bedroom from that point forward. He spent all his time with his longtime mistress, Diane de Poitiers.