You need to get your head out of your butt because not everyone is destined to salvation especially with the attitude that you are displaying ( seeking pity, giving up praying, lack of faith, etc.).
You stated, "One day, I was having these thoughts and I had some doubts and I actually believed one of these blasphemous thoughts about what the pharisees said about Jesus's miracles when they accused him of demonic power and I tried to rebuke it from my heart but it was too late." If you had faith in the God of the Bible, why would you believe that Jesus' miracles were performed through demonic power instead of the power of God through His Holy Spirit? God judges the heart of man and if you are stuck on a time of your ignorance where you entertained such perverted thoughts, it doesn't look good for you. I have to assume that you really were never born again. How do you " rebuke it from your heart"? The devil is constantly bombarding Christians with evil thoughts that the Christian recognizes as coming from Satan. We can not be held responsible for having them. What we are held responsible for is believing them and not dismissing them. I truely believe that you are on the road to recovery because I see the repentance needed for salvation. Now you have to totally put your trust on the love of God , Jesus, and the Holy Spirit. If you've given up on praying to God for His help, and I don't judge, but it doesn't look good for you. Prove yourself to God and persevere by continuing in prayer and having faith in His love.