 Stop allowing the assault of the enemy, which is accusation, to prevent you from prayer. 1 John 1 verse 9 tells us, if we confess our sins, he is faithful and just. Forgive us our sins and cleanse us from all unrighteousness. How much heartache could you save yourself in prayer, if instead of wondering if God has forgiven you? If instead of begging God to forgive you, you simply embrace the fact that he already has, and therefore you're free to move into the depths of prayer unhindered by your past.