@Hedrick - thanks, this is a balancing perspective.
Before I came to the faith and repented from sin, I had this same issue. I was very lustful and it was like a habit to me, but when I found god and he found me I was given this supernatural ability to cease sexual desires immediately. I didn't even think about returning to sex. There were times when I felt like I was being ravished in my sleep, but of myself I did not engage in sexual intercourse again. I haven't physically had sex with anyone since. I dropped addictions and never picked them up again when i came to God and I am thankful. The thing was; I had faith that I could do all things through him who strengthens me, and I could. I received this extraordinary strength to stop these things because I had faith. My friend, with all due respect, where is your faith in this? What excuse do you have, for after you came to Christ, you should have received the strength in spirit to put these things away. All I can say is you best have faith that you can indeed do all things through Christ who strengthens you. Why you did not have faith in this before, I do not know, nor do I know what hope you may have, if you have any at all, for those who go against the truth and deliberately continue to sin after coming to knowledge of it have no sacrifice that could possible cover their sins, but only expectation of fiery judgment. I really felt like you should have known better after coming to understand that as a Christian you need to abstain from sexual immorality especially before marriage.
For I can do everything through Christ, who gives me strength. -Philippians 4:13
This is what has happened to me too, though different from you I noticed a gradual change from seeing people lustfully to seeing their beauty but not thinking sexually about it. Of course the world is a beautiful place because God is a tremendous designer - look at the exotic birds of the rainforest, you don't need to think sexually about them.
I want to just emphasise that your comment "My friend, with all due respect, where is your faith in this? What excuse do you have, for after you came to Christ, you should have received the strength in spirit to put these things away." - I think you should respect that everyone has different circumstances, the gravity of our sinfulness varies. Ultimately when we come to Christ, we agree to let Him take our burden of sin and to train us in ways of righteousness. If that has truly happened then Jesus will act in good time.
For instance, it took almost a year for me to conquer my cigarette and alcohol addictions because there were more important things to learn first, but when it happened there was absolutely no way I could have used those substances. I am now able to drink responsibly like a normal person.
Also, my flatmate has just undergone the same training for his alcohol addiction, Jesus scared the crap out of him so it will definitely be a while before he drinks another beer. He is raving how strong the Lord is in his life and how much better he feels. So my advice is to make that decision "yes I want to cut this sin loose", hand it to Jesus and then quit worrying about it so much. I feel that DexterMorgan is right, if Jesus cares so much that you are living in sin then He will stop you, but it is really your decision to rely on Him and to listen to everything He tells you. Again, I feel that Hedrick spoke well and that ought to help.
One last thing, about that verse in Psalm 145:18, take note of this:
18 The Lord is close to all who call on him,
yes, to all who call on him
in truth.
Notice that praying is pointless if you don't pray in truth. You shouldn't need to pray over and over again for the same thing because God already knows your needs and desires. Instead surrender the matter in your heart - be comfortable with the prospect of surrendering lust. Until you are ready to surrender your desire to sin, Jesus will not force you to put it away. You absolutely do need to be willing.