I'd like to ask a question. But I must first tell you that I grew up going to the church of christ and my grandfather was a preacher. I got into drugs at a young age as my stepfather abused my mother and I when I was growing up. I finally surrendered all to God when I got put in prison the second time. God has done miracles in my life as he has saved me from myself and death over and over again. Right before I went in, I was baptized by my grandfather, and I meant it as I was tired of my life of sin that was destroying me. I was prescribed Xanax by my doctor became addicted to it. When I went to prison I got off them and never went back on them. I studied God's word day and night for almost two years. I began encouraging others and teaching others about God's word. I was so happy with zeal to work for God and righteousness sake. I had a new life and excited to see what God would do with me and in me for the future.
I was discharged a few months ago. Since then I wanted to become a preacher or do something great for God. I've been looking into going to a bible college. I saved up money and bought myself a car and got a job. My grandfather has been using me in the church training me to be a leader. I taught some Bible classes Sunday night a couple weeks ago and led songs Sunday morning as well. Since I've been out many in my family have seen a great change in me to God's glory.
Now I've been looking for a good girl to have a serious relationship with who would become my wife eventually. I met a girl online at the beginning of the week and I went to her house today. I gave into temptation and we had sex. Truly, it wasn't my intention when I went there. But I don't know what happened to me. I thought I wasn't like this anymore. I thought I had grown in Christ, able to not be overcome by such defiling sin. How could I be such a hypocrite? Immediately after I did it, I told her that I have hurt the heart of God and that now I'm in deep trouble with Him. How could I treat God this way after all that He has done for me? I got on my knees and pleaded with God for forgiveness and told him how I repent and ask that He would help me to change to never do this again. I told Him that I learned a valuable lesson, that even if I think I won't do it and a female invites me into her room at her house to talk and even kiss, I can't do it because I'm weaker than I ever thought. All the way back home I pleaded the blood of Christ on me and was so sorry to God I treated Him with such contempt. I told the girl I would not be coming to see her ever again and that it was my fault because I know God's word quite well and committed a deliberate sin against God since I'm way more familiar with God's truths. I told her we must both repent and never do this again. I left and we won't be seeing each other anymore.
My question is, is God still angry with me? How could I have done such a rotten thing as I'm supposed to be God's son born again into His family? I had done so well for over two years. I even turned away sex from a girl wanting me to come into her house a few years ago. I felt good about that victory. How could I have been so weak? Am I forgiven as I have obeyed I John 1:9? Since I knew better, what can you tell me? Could this sort of thing happen to a true Christisn? I thought I was.
"Be sober, be vigilant; because your adversary the devil walks about like a roaring lion, seeking whom he may devour. Resist him, steadfast in the faith, knowing that the same sufferings are experienced by your brotherhood in the world" (I Peter 5:8-9).
"Therefore let him who thinks he stands take heed lest he fall" (I Corinthians 10:12).
Have you considered why God placed these and other warnings in the Scriptures? Being a Christian doesn't make you immune to sin. It gives you the weapons and the preparation to combat sin, but the danger of sin is ever lurking. You mentioned I John 1:9, but consider the context of that verse: "If we say that we have no sin, we deceive ourselves, and the truth is not in us. If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness. If we say that we have not sinned, we make Him a liar, and His word is not in us. My little children, these things I write to you, so that you may not sin. And if anyone sins, we have an Advocate with the Father, Jesus Christ the righteous" (I John 1:8-2:1).
What makes a Christian different from the world is that the Christian will not allow himself to stay in sin. He finds sin repulsive, and so he works to change. "What shall we say then? Shall we continue in sin that grace may abound? Certainly not! How shall we who died to sin live any longer in it?" (Romans 6:1-2).
What happended is that God took advantage of your pride. You were thrilled to have left your old life behind. You have been making great strides in learning God's Word. You even successfully resisted sexual offers in the past. But those very successes made you lax. You didn't kept your guard up because you didn't think you needed to be so careful. The first time I read your note, as soon as you mentioned you met a girl online, I knew where this was heading. Why? Because a good woman would not trust a man she just met online. She wouldn't be inviting him into her house, let alone her bedroom.
If you are looking for a good woman to marry, you have to look in places where good women tend to be, such as at church.
I suspect that another reason this happened is that as a man you were expecting to be the initiator when it came to sex, so you were prepared to turn down offers. She probably came on strongly and you weren't prepared for that. A study of Proverbs 5-7 would be beneficial to you.
As I've told many young men, when it comes to sex, you can never trust yourself. Sex is a strong desire in humans and once aroused, people don't think clearly. See: How much sexual stuff is too much?