Sounds familiar.
My Gamerchick started by watching me Play Halo 2.
Even when I didn't want to play, she'd ask me to play. At first she just wanted to watch.
Now she plays more often than I do and she kix but too.
She has so many friends online, she now has 2 different gamertags.
Might have to get a Wii in the near future to satisfy her game fix.