Who is Donna Troy?

If the Amazons have been absent since Diana entered Man’s World, from where did Donna Troy come? And by whom was she trained? And why does Diana feel negative about her in the Titans annual with the JLA?

If she was force grown as a young adult by a witch for the Amazons (or whatever they were) in the WW title, how was a younger version of her running around with Dick Grayson Robin and the boys before her creation?

There are things the human mind is not meant to understand... Donna Troy's origins is one of them, or that might be because DC reflectively butchers her whenever she seems to have one.

Point taken.