Nah, I usually have this too with new female people I get to know, sadly, I never really found a cure other than to keep reminding myself that 'it's just a friend', and 'don't go thinking like that now'.
But yeah, I do know what situation you're in. Your only cure, as far as I can see, is try to not take it all personal what she might say about you, and don't show too much interest towards her either. It'll only disappoint you if you know you can't or shouldn't have her.
Sorry if I couldn't help much....