My Lord! Make me and those believers of my descendants keep up prayer. Our Lord! Accept my prayers.
Our Lord! Forgive me, my parents, and the believers on the Day when the judgment will come to pass.
[Sūrah ʾIbrāhīm, Verse 40-41]
Shaytan traps you in a cycle of misery, making you dwell on the past so you feel sad, and fear the future so you lose peace. Forget the past after Tawbah, and leave the future to Allah. Focus on pleasing Him, for Akhirah matters more than all your worries of Duniya.