Hey Jack,
Thanks for sharing, welcome.
For me, sanctification can be a long process. Repentance, for me, doesn't mean that I'll never, ever sin again. It means that I choose to pay attention to the part of me that wants to follow the will of God. I'm emphasizing the words part of me. Because there is still a huge part inside me, my flesh, my weak, weak, flesh, that desires many things that are evil.
This is my opinion. Being a "good" Christian shouldn't be about trying harder to be good enough. Jesus has paid the debt for all of my sin. And if I repent of my sin and put my faith and trust in him. That's it. My case is legally dismissed. I try not to overanalyze what it exactly means to have complete repentance and faith. Because, honestly, I don't think any human being on this earth has perfect repentance and perfect faith. (Roman 3:23)
So what about those times down the road when I sin. Well, I'm trusting that God work enough through me so that I can repent of those sins, accept Christ's sacrifice for my sins, and move in a better direction. And then there are days in which I feel I'm truly abiding in Jesus. So although my flesh and spirit are in conflict with each other, it's good enough for me to know that I'm not going to give up trying to please God. Just don't give up. Because giving up on repentance and sanctification is bad.