This book is very good, but very bleak. The state of the world at the beginning is entirely plausible, and the idea that the only thing that can prevent or undo it is the arrival of godlike aliens all too easy to accept. Yes, it would be very nice if some friendly aliens showed up and fixed everything - and this is certainly a more realistic portrayal of that concept than the more common options of utopia imposed without resistance, or spontaneous and unanimous raising of consciousness - but the basic premise is still entirely unrealistic. No one's coming to save us.

The only issue I had with the book otherwise was that the protagonists's

selective amnesia

is awfully convenient, allowing her to be the sort of person she needs to be for the plot to happen while being in a position that that sort of person would never be in.  It's fine though. It works.