Is it necessary to inform one's family about frequent wet dreams and bathing for ghusl, or should the matter be kept secret?

There is no need to inform your parents about wet dreams; it is a natural occurrence for adults. Occupy yourself with obedience to Allah and distance yourself from anything that incites desire. If your desire is aroused, occupy yourself with obedience, remembrance (dhikr), and sitting with the righteous, and avoid solitude and those who indulge in immorality. Increase your supplications, and humbly entreat your Lord, asking Him: "O Allah, I ask You for guidance, piety, chastity, and self-sufficiency."