here is a difference between fellowship and relationship. I'm related to many people that I now have no communication with at all. We have no companionship or friendship. We are related... that's it. I don't mean to say that blood ties mean nothing to me. I only intend to differentiate between being related to someone and being in a constant friendly conversation that involves mutual satisfaction.
In Psalm 15, David asks about the abider; the dweller. Who gets to abide in God's presence? Who is allowed to dwell with Him? If we are talking about relationship, we all fall short; nobody measures up (Psalm 14:2-3). There is not one man who has ever been declared worthy to be in God's family by basing his entrance thereunto upon his own moral merit (Romans 3:20 & Galatians 2:16).
On the other hand, our communion and fellowship does indeed fluctuate based upon our obedience or disobedience to God. We haven't moved out of the realm of faith or anything. It would be radical and absurd to imagine that we can be pure on our own now that we are born again (Galatians 3:3); it's just that God's expectations and our abilities are now parallel through the powerful and gracious presence of the Spirit of God... so, we have no excuse really (Roman 5 - 8).