What do you deserve? Confusion? Separation from God? Even death? Well, the bad news is that yeah, you probably did deserve it. The good news is that everything that you deserved, all your righteousness and unrighteousness, sin, shame, and offense, died on a cross about 2,000 years ago.
Look fully at what you've got yourself into, and see it on the cross with Jesus. Every sin in your life was dealt with 2,000 years ago. Every blasphemy you will ever utter was washed away in Jesus' blood. There is no longer anything that can keep God from you. A blasphemous thought pops into your head? Imagine yourself grabbing that thought and nailing it to the cross with Jesus.
Romans 8:38-39, NIV wrote:For I am convinced that neither death nor life, neither angels nor demons, neither the present nor the future, nor any powers, neither height nor depth, nor anything else in all creation, will be able to separate us from the love of God that is in Christ Jesus our Lord.
You don't need to beat yourself up over your sin - Jesus took the beating for you. You don't need to worry that God will leave you or ignore your prayers because of sin - that sin was crucified with Jesus. You don't need to feel separated from God - He will never leave you nor forsake you.
Just think of the God who has already dealt with your sin at the root, meditate on the fact that He's already taken care of your sin, and put your salvation in His hands. You now find yourself under attack not from sin, but from the idea that you are separated from God. This idea is false. You can, at any time, and from any point, look to God and say "I am yours; save me." He will answer.
