God will certaintly hear your prayers, all you need to do is reach out to him. Ask God for forgiveness and strength to carry on without falling into the sin you speak of. God is always there, all you need to do is reach out to him.
People that have given their hearts and lives to Jesus can live free from sin, however we aren't expected to be perfect. Jesus said to the adulterous woman in John 8:11 "go an sin no more." He didn't say go, be perfect and sin no more. So don't let yourself get caught up in condemnation because your life is not perfect. No one is perfect, we all have our baggage and stuff that gets us down. That is why we have Hope and Trust in a Living Saviour. Jesus lifts us up when we are down. Through Him we have strength to carry on in the darkest of hours.
For me, with Jesus in life He has given me the necessary strength to kick sin out. Do I slip up once in a while and say a bad word or react in a harsh manner...yes. But as for the sin that was ruining my life, and driving me into darkness - I just reached out to Jesus Christ and he brought me out of my despair, into light. Am I tempted...yes. But through the Mercy of God I'm forgiven when I do slip up.
I pray you find the answers you so desire, and may the peace and mercy of our Heavenly Father wash over you through Jesus Christ.