It is not incumbent upon you to complete the work (Ethics of the Fathers 2:21).
In economics, the bottom line measures success and failure. Someone who goes into a business venture with complete recklessness, yet makes a great deal of money, is considered a successful entrepreneur. Another person who was extremely cautious and applied sound business principles, yet went bankrupt, is considered a failure.
Unfortunately, we tend to apply these values to our personal, non-business lives. If things do not turn out the way we wish, we may think that we have performed badly. This is not true. If parents abuse and neglect their children, yet one child wins the Nobel Prize, or discovers the cure for cancer, they do not suddenly become good parents. On the other hand, if they did their utmost to raise their children well, yet one becomes a criminal, they are not necessarily bad parents.
We must understand that we have no control over outcome. All we can control is process, i.e. what we do. If we act with sincerity and with the best guidance available, then what we are doing is right.
Parents whose children turn out to be anti-social invariably fault themselves and may be consumed by guilt. Their pain is unavoidable, but their guilt is unjustified.
Humans do not have the gift of prophecy, nor do we always have the most accurate knowledge. We should hold ourselves responsible for that which we can control, but we should not hold ourselves responsible for that which is beyond our control.