What is the reason for suddenly abandoning prayer and worship after committing to them, and does listening to the Quran and sermons without benefit indicate an ongoing internal struggle?

Prayer is the second pillar of Islam after the two Shahadas, and it is the first thing a Muslim will be held accountable for. Whoever observes it will succeed and be saved, and whoever neglects it will lose. A severe warning has been mentioned for those who are lax concerning it, such as the Almighty's saying: "There succeeded them later generations who neglected prayer and pursued desires; so they are going to meet evil," and His saying: "So woe to those who pray, [But] who are heedless of their prayer." The one who denies the obligation of prayer is a disbeliever by consensus, while the one who is lazy about it is a matter of disagreement among scholars. One must hasten to repent and observe the prayers, along with making up for missed ones. If their number is unknown, then one should continue making them up until it is overwhelmingly presumed that one's responsibility has been discharged.