God forgives and He forgets. God's forgiveness is full, it's free and it's final.

I will remember sin no more, for I will be merciful regarding their wrong deeds, and I will never again remember their sins." Hebrews 8:12

Satan wants us remembering and feeling bad about the sin which God does not even remember. God is over it. He's moved on- it’s a new day. He only has mercy for you today, no thoughts of yesterday, He does not remember past mistakes and failures. As distant as the east is from the west, that is how far He has removed our sins from us. Psalms 103:12

God has dealt with our sin and our shame. Oftentimes we confess sins and we believe we are forgiven but we still feel some sense of shame. Shame hangs over us like a cloud. Many times we know we are forgiven but we don't feel cleansed. That feeling of failure and unworthiness Satan will seek to exploit. Regrets can be about what you think of your past. But God has made provision for not only our guilt but our shame too. If we confess our sins, he is faithful and just to forgive us our sins and to cleanse us from all unrighteousness. 1Jn 1:9

God only sees our failures as a lesson. A lesson in Love!. When Jonah failed God in his mission to Nineveh, the lesson God wanted him to learn was the lesson of love. When the gourd grew overhead then died, Jonah was miserable for himself, but Gods point was - shouldn’t I have had compassion on these people? Jonah couldn’t be a success until he learned to love like God.

When Peter failed three times, Jesus asked him “do you love me?” three times. The declaration of love was necessary to undo the sense of failure. When Peter was asked to feed the sheep it was to show love. The essence of success is love.
Friend failure is only ever a failure if the lesson of God love for us and others is not learned. Love never fails and love re-stores failure.