I admit, although there are times I think I am making progress, on the other hand I feel like I understand nothing and am in darkness. I'm at the point where I am very very aware of my sins, particularly one which I can't get much control over.
I feel defeated and that God is shaking his head at me and is not happy with anything I do. I don't grasp God's love and mercy for me. I believe the Gospel message and I believe on Jesus Christ to the best of my ability. But I have no joy in my life because I am trying so hard to believe in God's love for me, and I just utterly fail.
I guess I'm looking for words of comfort and maybe someone who has gone or is going thru the same things.
The mistake you're making is that you think Gods love is conditioned upon your performance, when scripture says that even while we were sinners, Christ died for us. That is the heart of God displayed for all of the world to see. God loves you enough that He sent His Son to die for your sins, and even if it was just you, He still would have done it. There is no way you could believe He doesn't love you if you would only acknowledge the sacrifice of His Son for you on the cross. Jesus took your punishment upon Himself so that you could be reconciled to the Father, and His blood is the provision for your sins:
1 John 1:9 If we confess our sins, he is faithful and just to forgive us our sins and to cleanse us from all unrighteousness.
The devil is trying to get you to believe a lie, that you are condemned. When Jesus died on the cross He said "It is finished". You are Gods child, and the blood of Jesus covers your sins. Notice it says that when you confess you are cleansed from *all* unrighteousness? That means you are holy and blameless in His sight. Do you think the blood of Jesus is not sufficient to cover your sins? That is what you are believing when you think you are too bad for God to love you. That is one of the devils favorite lies to tell Gods children.
You don't need to believe in Gods love, you need to receive it. You need to understand it as a fact based on Gods truth and not based on what you can do for God.
There are two reasons why you are stuck in your sin. The first is that you haven't let it go. You are still holding on to it and making allowance for it in your life. You have not yet completely agreed with God about your sin and turned your back on it. That is why you are being defeated over and over again. The second reason is that you are trying to do it under your own strength. You said things like "I am trying so hard" and "the best of my ability" and so forth. The fact is that your best is not good enough:
Isaiah 64:6 But we are all as an unclean thing, and all our righteousnesses are as filthy rags; and we all do fade as a leaf; and our iniquities, like the wind, have taken us away.
Our righteousness is like filthy rags to a holy God. There is nothing good within us apart from Christ. That's why He said this:
John 15:5 I am the vine; you are the branches. Whoever abides in me and I in him, he it is that bears much fruit, for apart from me you can do nothing.
Apart from Him you can do nothing, including overcoming your sin. Your belief that God is turning His back on you is what is preventing from receiving the help you need. God put His Spirit IN you to help you and teach you, to make you a new man. You are not distant from God; He lives inside of you and He wants to help you overcome these hurdles, but you have to be willing to surrender to His control. You can't free yourself but God promised to free you from sin:
Micah 7:19
He will again have compassion on us;
he will tread our iniquities underfoot. You will cast all our sins into the depths of the sea.
Are you ready to stop fighting this battle under your own strength and surrender? That is where victory is, because Christ already won this battle at the cross. You are trying to fight against a defeated foe; Jesus wants you to step into the victory He got us at Calvary by submitting to His Lordship and letting Him fight this battle for you.