It’s a shame being too insecure about abandonment becomes the reason someone will break up with you. It becomes a self fulfilling prophecy.

She may be given some diagnosis if she sees a therapist about it.

I’ve been given a diagnosis along the lines with what your gf is dysfunctional about. However I’ve never been unreasonably insecure, clingy, or jealous.

I suggest you have an honest talk with her to say how her insecurity is unfounded because you care for her. Then if she doesn’t let up, another talk about how her behavior is not working for a relationship with you. Don’t play into it. She may not be right for you then. And you will break up.