I once believed, but I rejected God. What do I do?

Our Listener says, “I understood and accepted the message of the Gospel in 2013. I grew for a while listening to sound sermons and I had security of my salvation based solely alone on Christ’s finished work and none of my own works contributed. However, I made poor decisions and I rejected God in 2020, and I have been in doubt my faith conversion was genuine. I lack love and thankfulness towards God, I don’t believe I am being chastened when I sin, and no matter how often I read the Bible, I get no peace. Almost everyday, I am tormented with the belief God has given up on me and I’m going to hell. I have sought him in prayer many times. Please can you offer me some advice and point me in the right direction? I must reiterate, I did believe the gospel in 2013, but I no longer believe. I want to believe the message again because I know it’s the only thing that will give me a secure foundation to grow in faith. Thank you for your time in reading my message.”