This has become such a hindrance to us being happy that I sometimes wonder if it is best to stay with her to try to help her through this, or whether I am out of my league. Dear Reader, Your girlfriend can go to a counselor for a while and learn to manage her feelings. She can do some research to find a counselor or group that specializes in treating people who have been abused. In that safe, supportive space, your girlfriend can talk, learn, and set her own agenda. With help, the strong, fearful feelings do not have to last a lifetime.
Healing takes time and requires courage to face the beast.
If your girlfriend does not take the opportunity at this time to make some of the important changes in her life, then it may be that she is not ready. You, in that case, have some choices to consider, including cutting your own losses and moving on.