Job is my favorite as well, along with Romans, James, and John.
Glory to God! This is a battle of good vs. evil, the same battle that has raged through the ages. The kingdom of light vs. the kingdom of darkness.
Jesus, through perfect obedience to God the Father, has already won. The enemy knows he is a defeated foe. Praise the Lord and bless you, fren.
The quick answer is the Bible does not talk about forgiving oneself. The good news of the gospel is God's free gift of salvation through believing in Jesus and His sacrificial death on the cross. Forgiveness is a free gift, and the Lord is where you put your hope, faith, and trust. It truly is amazing grace. When past sins become overwhelming, look to Jesus.
Amen!