Sounds like a nest of narcs, and your lady is the scapegoat in the family, with very enmeshed and controlling relatives. Sounds like they also did the infantilization thing heavily, too.

It is extremely unlikely that this is something you can fix.. as far as healing her or helping her "see the light". The behavior of your lady.. that sort of behavior at its core is done out of deep, terrible fear, likely instilled in her from birth. By adulthood, it is deeply buried in the subconscious and has morphed into a deep, severe terror that standing up to or breaking free from the abuser(s) will result in death. That probably sounds very dramatic, but remember that these things are instilled when the person is a young child.

Therapy is her best hope. Even better if you two can attend some sessions together, as a couple.