Eek, you're one of these people who doesn't speak english! Oh well, hopefully I understand enough of what you said to reply.
It's really difficult when you're friends with someone like that. I have a friend who's similar, and I feel very frustrated with her at times.
When your mate's acting competitively, does it make you feel like you want to play better than her? i.e. do you feel like competing back?
What would it be like for you to talk to her about it, for instance to say "I get a sense that you want to be a better player than me, and that makes me feel sad because it gets in the way of our friendship." ?
Good luck with it.
Amber
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