It'll also depend on how much interaction she has with him once he arrives. If she doesn't see him at all, you're probably okay, if she gets in touch with him, you probably have to worry a bit, and if she actually hangs out with him "as friends" then you should probably break it off before she either dumps you for him or cheats on you with him.
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~Halo Time to rock, Scott Pilgrim style.
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