Yes but it kind of effects me too. She was at my house yesterday and she took one of my games. Ever since I got it back mine has been doing the same thing, and I wouldn't be surprised if she duplicated some of my stuff because on a number of occasions she's asked me to give her some rare items and I refused. It just turns black for a few seconds whenever I'm in the train station or in my own town with gates open. Sorry for not mentioning that before.
She really messed me up yesterday because I had 2 dreamies in boxes and no town to send them to. I couldn't cycle or do any trades until I got it back later that afternoon. But when I got it back it was kinda messed.
Honestly im not sure HOW close you guys are to eachother, but if she keeps messing up your game just dont let her use it. I know you may be very good friends, but sometimes you just have to stand up to even your closest friends.