God's mercy is endless, from everlasting to everlasting! His Love and mercy and forgiveness and Salvation never end! He never stops loving us no matter what we do. He never rejects us nor withdraws His Love. He always has hope for us no matter how far we've strayed. (Psa.103:3-14)
Even in spite of our sins and shortcomings and misdeeds and crimes, whatever they may be, the blood of Jesus covers all our sins, past, present and future. If we will forsake our sin and turn to the Lord, our God shall abundantly pardon. (Isa.55:7) The Bible says, "If we confess our sins, He is faithful and just to forgive our sins." (1Jn.1:9)--No matter what we have done! The only "unpardonable sin" is a refusal to believe in Jesus, rejection of Him as your Saviour.
But most people do not suffer for the unpardonable sin, but rather for pardonable sins from which they fail to repent and ask for forgiveness.
We have a God big enough to forgive not only our mistakes but our sins! He always has and always does and always will, forever and ever and ever! Like a stream, like a river, His Love and mercy just keep flowing no matter what!