Beyond Selidor

Oh boy, the Axis trilogy, and as a preteen no less! That's ... a lot! I think I only bothered reading it once (the Troy Game series was my first encounter with her, after which point I read everything I could get my hands on, which I don't think would have happened if the Axis books had been the first of hers that I'd read). Two things which made a lot of stuff about Douglass's writing in general, and the Axis books in particular click into place, which I gleaned from various interviews and blog posts by her back in the day:

She wanted to be a medievalist academic researcher, but came from a conservative working class family who felt the only acceptable career paths for women which required higher education were nursing or teaching ... so she became a nurse in a gynaecological ward and encountered a lot of horrific stuff; and
The Axis trilogy was her first published fiction, and it attracted an intense and rabid fanbase who disagreed strongly with her on shipping matters, preferring the female character Douglass despised and disliking her Strong Female Character™ that she had designated as the reward/love interest of her series' hero — and Douglass made no secret of how much this irritated her.

Even the first time round when I read her books in my early twenties, I got the sense that she was working through a lot of issues relating to the above in most of her published fiction.