ANSWER: We have all lost our lives to Satan, which is why Jesus had to come and literally buy us back or redeem us (Galatians 3:13). Jesus specifically bought us back from the devil. God, through Christ, owns us now and not the devil.
In Matthew 12 Jesus taught that EVERY sin and blasphemy will be forgiven by God (Matthew 12:31 - 32). The one that is not forgiven is commonly referred to as the unpardonable sin. Basically, this sin is unpardonable (not forgiven) because a person WILLFULLY (and not out of weakness or deception which we can all fall prey to) REFUSES to ask for a pardon!
Our heavenly Father wants to save everyone (1Timothy 2:4). The only question is how much pain do we want to go through before we decide to believe him and not the devil. In Hebrews 12 Paul says God, as a loving Father, corrects every person He works with and considers on of his spiritual children (Hebrews 12:5 - 10).
Satan's will is to have you think how bad you are and to believe the Eternal does not love you. No matter how sinful you are God ALWAYS loves you and will allow you to go through as much suffering as is necessary to finally believe Him and not His adversary. He wants us to repent (Acts 2:38), which means to change our mind from seeking the will of the devil (e.g. which is to NOT forgive yourself after you have been forgiven) to His will.
In his Sermon on the Mount, Jesus said that if we ask the Father for something (according to His perfect love and will) He will give it to us.
'Ask, and it will be given to you; seek, and you will find; knock, and it will be opened to you. For everyone who asks receives, and he who seeks finds, and to him who knocks it will be opened.' (Matthew 7:7 - 8)
It is God's will that we ask for forgiveness. Although He knows we are weak and sometimes give in to the temptations and deceptions of sin, He promises to ALWAYS forgive is we ask. And he also promises to eventually remove all traces of sin within us (1John 1:9).
When you pray, ask Him to help you believe Him and accept His forgiveness no matter how bad you think your sins are. Belief (faith) in God can lead you to repentance.