Was Camilla a courtesan before she married Charles?

I doubt she ever had the looks or personality to be one of les grandes horizontales.

Camilla was a mistress. That was many years ago. They have been married since 2005, spending more time as a married couple than as lovers.

People who obsess over the past are biased and judgmental.

Charles may love her, but the public doesn’t. And even Charles only tolerates her because she is perceived as being even uglier than him, does not steal his limelight, and soothes his fragile oversized ego.

Prince Charles has been with Camilla forever, it's time to move on. How long can you cry over spilt milk before you look silly. It's done. They love eachother, sacrificed their reputation to be together and they're still standing. Let them live their life in peace, especially after this many decades. 

A courtesan in eras past was a professional mistress to royalty or the high nobility -- people who frequented royal courts.  They don't exist any longer. There's no need for them.

Camilla was just Charles's lover, the woman he should have married and eventually did.

No, just a woman who had been round the block a few times...and then some.

Taking the literal translation for this -

"What is a courtesan relationship?Courtesan, in modern usage, is a euphemism for a prostitute, particularly one with wealthy, powerful, or influential clients. The term historically referred to a courtier, a person who attended the court of a monarch or other powerful person."

Camilla was not.

Now that royalty is ending, some royalists are now showing the true face of this dreamy fairy tale they were hiding behind from. They think that anonymity will change something. 

No, she was someone he loved but was pressured into not marrying her because she was considered unsuitable. That was due to her being older than he was and she was not a virgin. Then he was pushed into a marriage to Diana, a woman he never loved.

When you became an idiot.

Did it happen suddenly.

Gradually

or have you always been an idiot.