How can one escape the cycle of guilt and despair and return to hope after committing a great sin in the past, especially when praised by family and adhering to religious practices?

However great the sin, the forgiveness of Allah Almighty is greater, and His mercy encompasses all things. Whoever repents with sincerity and truthfulness, Allah will accept their repentance, for "the one who repents from a sin is like one who has no sin." Allah Almighty says: "Say, 'O My servants who have transgressed against themselves [by sinning], do not despair of the mercy of Allah. Indeed, Allah forgives all sins. Indeed, it is He who is the Forgiving, the Merciful.'" As long as you have truly repented, then be confident that Allah has accepted your repentance. Turn to Him, striving diligently in obedience and increasing in good deeds that expiate sins.