Second Shift by Kit Anderson

From the time when the station wakes her up, Birdie Doran is on the clock. It's just her and one or two others on Terracorp's isolated outpost, processing comets. So she slips into virtual reality, with the station creating adventures for her as she does repairs, routine maintenance, and checks the status on all the systems. But when Birdie discovers another abandoned station just within walking distance of her own, she begins to question her isolation, and her own memories of what her job-and her life—really is. And at every turn, she starts finding the things the station has been hiding from her. Ignatz Award-nominated author Kit Anderson presents a psychological science fiction exploration of the lines between reality inside and outside the mind.