just forget about her, i had a "friend" like this once. Ill leave out the details tho, as despite what i say below, id still rather not get busted should our paths ever cross again (which ive learnt, is actually very likely)
anyway cut to the chase (im a guy), We met by chance and fell for each other in a very big way, but lived opposite ends of the country so could only be friends. Soon after we met she went through a very bad time and i was the first person she came to for help (before even her parents) so i tried as best i could, (and repeatedly told me she was grateful and i was, quote, "a really good friend"). We did meet up a couple of times, One day though we decided and agreed it would probably be best to put a bit of distance between us as we still liked each other a lot (well...she said she did).
A few months later i txtd her a couple of times just to say good luck for her AS exams and see how things were going for her, and straight from the mark she just replied by throwing back everything id ever said to her try and help her, I tried to reply and ask exactly what i did wrong so i could apologize, but just got txts that hurt me more than i thought possible. Whether she was going though another rough patch or not i dont know and tbh dont care, as there was and is no excuse for what she said.
THEN, about 9 months later (~10 months ago) she randomly starts talking to me over the net like we'd been best friends the whole time, but having tried to email her a couple of times since just to try and patch things up a bit (before our paths inevitably "cross again"), once again we havent spoken.
My advice is quite simple though you probably wont like it:
Give up and forget about her m8, some gals you think are fairly normal when you meet them, just turn out to be two-faced, immature b*tches who just think the whole world owes them a favour.