That's fantastic Zeus! I've returned from a weekend camping trip feeling a little discouraged but God knew this and lead me to your post. You see I've prayed to be used as an instrument to do His will...to bring His children home to Him. Amidst all this chaos that's going on in my M, I asked God that He use my experience to affect others and bring those people closer to Him during their time of need. I was reluctant at first for fear of sounding preachy but he pushed me to share my experience with you. Your picking up "The Power of a Praying Husband" is proof that God listens to our prayers. I prayed for your sitch and hoped that in your desperation you would seek Him. Yeah, it's just a book...but change begins with one tiny step. You are well on your way to spiritual healing.
It's natural to feel unworthy of God's grace. How can we still be loved and be forgiven for all the wrong we've caused? I struggled with this too because in my mind I had caused so much destruction that I felt ashamed. But then I learned that how we (humans) perceive sin is not the same as how God perceives it. We operate on the idea that sin is measurable...one sin is greater than the other. God on the other hand sees all sins the same way. Kinda of like an imaginary line...once you've crossed it, you have sinned. But know that no amount of sin is unforgivable. Jesus gave his life for all humans to be saved from their sins...every single one of them--you included. So don't look at your sin as something to be measured but something to be redeemed from. We are all born as sinners and because of this we will continue to sin. So be prepared to be tested even further now that the enemy knows where you are heading and what you have discovered. These testings will come in many different forms...work, kids, marriage, friends, finances, health, you...
Furthermore, as you strengthen your walk and relationship with God, you will discover that sin will start to lose it's power over you. That is, there are certain things (like porn) that you will be able to turn from and know without a doubt that God has given you the strength to do so. He will also reveal to you that your body is not your own but belongs to your W and conversely her body is not her own but belongs to you. You were made man and wife to fulfill each other's needs rather than "I'll get mine because she's not giving it to me." It's truly profound...
I hope that you continue in your walk and that you find God is sufficient enough to get you through your pain. Please, provide updates when you can. It encourages me to push through another day. If need be you can always send private emails to anyone on this site that has enabled that feature on their profile.