Honey, if you have a group of friends that meet to have an 'all girl' party, and they are not shy about exhibiting their preferences, ask her is she'd like to join you at one of these parties. There you'll be able to check her reaction to what she senses. You'll be able to tell if she shows interest or is repulsed, and will have to accept her attitude. It's better than always wondering and you'll be able to go on with your lives. You can then reassure her that you are ready to accept her as just a friend if that's all she can give.
At any rate, you'll no longer be in doubt.
Good luck dear, and keep us posted.