Maybe it's because Roast Beef isn't so much a nickname as an "alternate" name. I dunno. It still makes me do a double take when I see it.
Have I missed something here? I thought Beef's name was Roast Beef Kazenzakis, no? If so then Beef
is his real name. What else is she going to call him!?
Also, everyone I've been involved with since I started using this name (almost three years ago) has called me Slink, though when I formally changed it one girl did decide she wouldn't call me it. She utterly failed to however, as she had always called me Slink. I guess there's no real differentiation between anyone I know, in terms of how they know me.
Also, in terms of the example given, and similar instances, I would think it happens because the new partner came from outside the group of friends who use the nickname, and thus they would have to learn a new name. I am back in touch with someone I was with before I started using this name, and she's finding it really difficult to refer to me as Slink when I'm not around, simply because it's new to her.