Your gf probably has to see someone that can help her understand her feelings, then deal with them in a constructive fashion. It is very common that people feel a bit out of control of important aspects of their lives at one point or another, needing some guidance to regain control little by little and gain self confidence.

Psychotherapeutics are good at this but you should not underestimate what your local priest can do, or similar persons you trust and you feel are old and wise.

The point is you most likely will need outside help, it is difficult for a person that is so heavily involved and emotionally attached as you are to be able to help her realize what she can do to help herself.

As previous posters have said, she needs to *want* to be helped, to seek help. The best you can do, IMO, is to encourage her to seek help and try to make her perfectly comfortable with it.