Channing. I am not a pastor, but I wanted to respond. I hope that's ok.
The good news is this: You are here seeking Christian help and that is what God WANTS us to do. It is in our bad times; sin, fear, faithlessness that we seek out God. That is when He works in our lives....IF we simply ask. He wants us to ask for Him and your are doing that.
Christ died so our sins would be forgiven, that was the whole point of His suffering. That was the whole reason God sent Him to us. Don't allow yourself to dismiss that great thing the HE did for us. Accept His freely given grace and forgiveness. It says in the Bible that everything we have done, are doing now, and will do in the future, is already forgiven. How wonderful!
Your only job is to understand what you did and know that it was wrong, and let God know you want His forgiveness. Oh... and you have to figure out how to forgive yourself. Sometimes that's the part that trips people up.
I love the story of Peter. Jesus told him he would deny Him and Peter didn't believe that he would do it. And then he did!...THREE times! Peter was distraught over his betrayal of Jesus, and could hardly accept that Jesus had already forgiven him.
Take care. Know that there are people out here praying for you. Gail