*shrug* I doubt very much it will break up the friendship. Especially if you start both watching other versions of Holmes as well and talking about the ins and outs of AUs.

Pretending something that isn't true gets tiring really quickly and isn't worth the effort in this case. Tell her. If nothing else you can say that you need a dose of something Holmesian on a regular basis until the BBC does a new series because you've overdosed on Reichenangst!