What is the advice for someone who repeatedly makes mistakes with young people after repeated repentance, and feels like a hypocrite and distant from God?

A person must remain steadfast on the right path. If they deviate, they must repent and return, for Allah Almighty has legislated repentance to forgive deviations. There are religious and worldly reasons for abandoning sin. Among them are fear and shame before Allah and the desire for Paradise. Among them are also the fear of scandal in this world and the sin's impact on studies, or being drawn into something worse. What helps in abandoning sin includes: occupying oneself with obedience, remembrance of Allah (dhikr), reciting the Quran, and not being alone too much. Most importantly, one must cut off all means of communication with those who invite to sin.