Pslams 103:12 says, "as far as the east is from the west, so far has he removed our transgressions from us." This verse can reassure that after you confess once, your sins are erased and forgotten completely. These verses should give us complete confidence in our cleansed heart and the renewal of our pure spirit, however because we are human, the hardest part is often forgiving ourselves. For some reason we cannot comprehend why a loving and just God would choose to cover our sins with the blood of his son and accept our faults with open arms. However, it is true.
"For God so loved the world that he gave his only begotten son SO THAT whoever believes in him will not perish but have everlasting life."
"but God shows his love for us in that while we were still sinners, Christ died for us."
God sent his son to die for you SO THAT he can forgive you and restore your life to the fullest! (John 10:10) So trust him in spite of your doubts. Claim one of these verses as your own and quote it over and over again until it becomes real to you. When you doubt, listen to the promises of God. He wants you to live in freedom, not bondage forever! (Galatians 5:13)
Perhaps this song could help you too. When I have trouble understanding God's forgiveness I play this on repeat over and over again until my heart believes. The lyrics are shown true in scripture, so this is God's promise to you. Be set free my dear sister.