You do realize that you don't even know half the sins you commit in a day.
Same with me and every other Christian. We can't possibly be "absolved" of them all by talking to a priest prior to Communion.
All Scripture requires is us to discern the Lord's body rightly, which means to take the occassion damn seriously.
The man who kept the memento wafer obviously did not, and I feel he probably is drinking judgment upon himself for his loose treatment of the sacrament.
However, all that must be done is for us to discern our hearts and the Lord's body, what he did on that Cross.
Nobody can be perfect when taking part.
Oh....but you CAN be absolved....if you repent. Sad to hear that you don't think you can be. Jesus gave THIS Sacrament to the Apostles also....."whatever sins you hold bound are bound and whatever sins you forgive will be forgiven".