Repentance = sorrow, confession, restitution and forsaking the practice. Acceptance from God comes upon repentance. In other words, it's conditional.
The ultimate goal is to stop the sin, not excuse it by blaming it on a fallen nature or weak flesh.
Some sins we can be totally free from. Fornication and adultery, for example.
I know what repentance means and I also know what forgiveness means. To disallow a believer to not commune with God because of a past sin which has been repented of is not an organization to which I would like to worship with. Makes God out to be rather small and petty instead of large and loving. I know which kind of God I'd rather believe in, thanks.