If all the people of the world vanished except the one person you love, wouldn't that be just fine?
No? Like really REALLY no? I mean, leaving aside that the entire point of this book is that she misses her sister and so her girlfriend isn't the one person she loves, but rather just one of the people she loves, we live in comfort and confidence because society has a number of safeguards that help protect us from the odd accident. Or a bad flu. Or an animal attack.
Honestly, reading these stories is kind of nervewracking, because that gun COULD have exploded. It hasn't been serviced or cleaned for years. Machines don't just stay in pristine condition indefinitely, and their world is a litany of unsuspecting dangers. They also don't know how to handle a gun, and there is no medical aid if somebody accidentally gets shot. And if the -one- -person- you have dies, there's no moving past that and finding someone else, like you can in the real world. There's no coping and waiting for things to get better and turning to other friends or family.