Hey Rubes, I don't like the term either but sometimes it's difficult to find something appropriate when relating to your 'other half'
I always write fiance but sometimes I think it sounds a bit soppy and comes across as a reminder to people that we're engaged - in an annoying way!
So as catty cat said, boyfriend is a bit kiddy, he's not my husband, I refuse to be called 'the missus,' ...he's so much more than a partner and although I'd love to do it, I'm sure he wouldn't appreciate me referring to him as 'my lil snuggly bum' or something along those lines.
(hope he doesn't read this!!) :o\