It's probably because I'm not as emotionally invested in the characters/people they are written about. Maybe; that happened to me in fictional fandoms, at least.

I don't think I've ever seen such AUs, and when a non-AU story avoids mentioning real-life (or fictional-life)SOs, it always feels kind of wrong.

(since I keep complaining about me and RPS, I may as well mention that I have the problem of wanting a het pairing for someone gay IRL - that sort of feels more wrong than vice versa)