The assertion was that he didn't stand up to pressure. That the pressure was from a royal to whom he was very close and was giving him selfish advice because of vested interest, and not his parents or the Archbishop of Canterbury, doesn't mean he didn't succumb to pressure. Or that she thought he went dark because of it and went on with her life.
He ended up succumbing to pressure: he just ended up marrying v2 of Mountbatten's formula when he was older, after v1, with self-awareness, declined. I remember reading accounts in the US that he needed to find a virgin, or at least someone without a "troublesome past," which was a lot tougher in the '80's without finding someone very young, and eliminated many women with whom he had something to talk about.
If only his parents had been nurturing, Lord Mountbatten might not have been such an influence