Charles was not allowed to marry Camilla, the woman he loved. She had too much of a 'dating' history and the palace decided he should marry someone who was younger who had not been dating.
Obviously they regret that decision now.
I know that..but if he had not dithered and had got to the point with Camilla before she could have had such a “dating history” things could have been different.
As I understand it, the Royals of the era didn’t want an other side of the blanket sibling to surface so the bride to be had to be “untouched” so to speak.