As someone who also suffers from abandonment issues, I'd like to say you're better off.
She's projecting her father abandoning her onto you and being manipulative as to make sure you will never leave her. Which is a narcissistic trait, but then I don't know her personally.
She needs to learn how to not project her father onto every men she knows. She also obviously have severe self esteem issues for not understanding that you have had a life before she came along and that your past is what shaped you into who you are now so there's no point cutting it out of your present if it doesn't harm you.
You could teach her that and be patient as well. If she was willing to go through therapy, but if she thinks she's in the right then you're doomed for a toxic love/hate relationship.