my say; just tell her how you feel. she is your best friend right? if so, then she will respect and understand your feelings. if your friendship is strong enough, you guys will pull through it. who knows, somewhere down the track you might even find out that she feels the same way about you. not a guarantee..but its worth a shot. friendships are based on trust...and as you mentioned, you are lying to yourself..and to her. dont put yourself through it just for the sake of 'keeping things as they are' cos its the safe thing to do. if she chooses not to be your friend when you tell her how you feel, then i dont think she's worth the trouble. be true to yourself!!
"We all take different paths in life, but no matter where we go, we take a little bit of each other everywhere."