Is the death of one's wife, which leads to the husband's return to the path of God through prayer, night vigil, and reading the Quran, considered sufficient for repentance?

May Allah have mercy on your wife and accept your repentance. Know that repentance is accepted, Allah willing, as long as it is before the death rattle and fulfills its conditions: abstaining from the sin, resolving not to return to it, feeling remorse, and restoring rights. Thus, you become like one who has not sinned, for the Prophet, peace and blessings be upon him, said: "The one who repents from a sin is like one who has no sin." Strive to draw closer to Allah and increase in acts of obedience, for good deeds erase bad deeds.