How can a married woman return to obedience and abandon bad habits, such as abandoning prayer and obligatory fasting, practicing masturbation, and committing to hijab, especially since she fears dying in this state?

Allah accepts the sincere repentance of His servants. The questioner should maintain the regularity of prayers at their prescribed times, for prayer is a help in fulfilling needs and atoning for sins. The hijab preserves one's honor and protects from dangers. It is obligatory to make up for missed fasts, especially in winter due to the short days. One must abstain from the bad habit [masturbation] and seek chastity through lawful means. It is preferable to engage in reading the texts of the two revelations (Qur'an and Sunnah) and stories of the prophets, to seek righteous companionship, and to frequently ask Allah for guidance, recite the prescribed adhkar (remembrances), and supplicate.