Salaam ya akhi,
I'm directly quoting from Mufti Ismael Menk who has quoted from hadith: despite doing fard and good deeds if you happen to sin then on the day of judgement your good deeds will be given to the person you have wronged and his bad deeds will be transferred to you. So its much more severe than losing your good deeds.
Some sins are forgiven but only if u repent which I'm sure you are aware of but then if u go back to it Allah will not accept your repentance.
However, quoting Mufti Menk again, instead of using the fear of Allah's (SWT) fierce punishment as a means to keep u on track I feel you should be more worried about losing His Love, His Rahma, because first the love disappears then the pain comes down on us. His love and guidance is enough to keep us on the right path. 1) Make constant dua for yourself, esp during asr, fajr and tahajjud. Fast the optional fasts. And last but not the least stay in wudhu 24/7. I can guarantee you that shaitan will steer clear and the angel that you have been appointed with since your soul was breath into your body will be a constant source of guidance from Allah (SWT).
May Allah (SWT) keep you strong and on the right path.
Originally Posted by .alhamdulillah.