It is my belief that the door is closed permanently when we face G-d in judgement after death. If, at that time, we have not become His, then we may never become His.
However, I understand your belief and will not challenge it too strongly. Your ending is also a good one.
Shalom.
the door is closed permanently when we face G-d in judgement after death...
We are certianly in agreement on that point... My only disagreement is that our Lord will never display the human emotion of exasperation the rich man showed with those who cannot follow a simple plan (until, as you point out, it's too late)...
I tend to believe as you do. There will be a time that we can not make the decision if it has not already been made.
We should not wait until it is too late.