That shows that Charles and Camilla are the same as any other person, in that aspect: they wanted to make their relationship official, despite the public outcry. Even if I never liked them, I recognize that it was their right. Now, about what would had happened if they didn't marry?
She would still be "Mrs. Camilla Parker-Bowels - the Prince's Mistress". What Charles did, actually, was to spear her the disgrace to be with him and being outranked by everyone around him...
The UK does not recognise defacto relationships - that's an Australian thing. So he could have continued in a relationship, but it would not have been recognised and Camilla would not have held any kind of title. It would also have made it awkward for Camilla to be involved in any official functions or to be given official travel, protection, etc.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.