Have mercy on me, O God, according to your unfailing love; according to your great compassion blot out my transgressions (Psalm 51:1 NIV).
There is no cry that God will listen to more than this one. There is a sure answer to this heartbroken cry. God would stop all other activity to listen to this cry of yours. For He is a God who longs to show you mercy. And when you cry out thus, God overwhelms you with His love. He will wash you with His love and lash your soul continually with His compassion.
He knows that you have sinned. He knows that you are now brokenhearted. He knows the pain and the shame and the remorse that bites your heart now. He knows the blackness of the deeds you did. He knows the foulness of all the thoughts you had. He knows the coarse and bad things that your mouth spoke of. He knows it all.
Be comforted. You are appealing to His unfailing love. It fails not! You are asking God to blot out your transgressions. Oh, for sure He will blot it out of His mind!
Only do not stop crying. Keep on pressing towards His heart: Till and until you know the touch of the hand that wipes all tears away. Stop not till He whispers your sweet name and comforts you like no mother on earth can do. Even then you have just floated on the surface of His great compassion. Dive deep into the ocean of His love. Drown in it. Then you will die to sin in your life. And you will rise up again with His favor encompassing you. Only one memory will remain: That He has indeed loved you with a compassion that never fails. What love!