ten to one it's thrush. any place where skin constantly touches skin and you get hot/wet, you can breed bacteria. i've gotten it in my bra more than once, and i've heard of people getting it in the folds of their legs/crotch. alcohol isn't going to help. think of it as a diaper rash. ball up some toilet paper and cram it in there to keep your skin apart and soak up any moisture. do that for a day or so and it should clear up.