Kylo killed Han. He can never be the 'good boy'. Not even the 'forgiven boy'. He can ultimately sacrifice himself though to save Rey from the big bad evil -- just like Vader did to the Emperor -- which would at last make him as "powerful" as his grandfather which is exactly what he wants.
That my friends is JJ's great arch for the character. It was written in stone in TFA.
That my friends is JJ's great arch for the character. It was written in stone in TFA.