Jack, this is what I was talking about by the way. Situations like this.
Here is the deal, you want to trust her and be with her. You already know you can move on, we don't have to tell you that.
For that, man...You've already told her about boundaries and she crossed them. I read a post on here about the use of boundaries, and jack and I have been talking about handling arguments and people testing your boundaries.
Most advice posted in this thread already can not be applied in your case. You do not want to just cut her off, she's one of those people who are close to you that test your boundaries. After you make the boundary transparent she will respect it for a while, and then test it again, even if you are transparent in your desire that you don't want this to happen.
You think she is quality enough because you made her your girlfriend, and you are trying to control and fix these issues before they spiral out of control, so I won't tell you to just cut her off.
I will say this though, you need to evaluate why you think she is quality enough to be going through this. You clearly don't trust her, and for good reason...
She doesn't seem to trust you for no reason and as Daario Naharis said: "People who think like that, I find that they themselves are untrustworthy."
So think about what qualities she has that make you want to keep her around. Make sure you haven't just fallen for a
warm body.
Now, if after you reflect on that link and determine she is a quality woman, then we address the problem at hand.
The trust issues, and her crossing boundaries that she knows is there. You are looking for a way to get her to respect your boundary, and make her trustworthy. Many guys hear deal with their boundaries being crossed by getting rid of the offender. If this is one of those hard boundaries that you absolutely do not want to be flexible on then most see the only way is to get rid of her. Because if she crosses it and gets away with it, it will become easier for her to cross it more and more.
There are articles written on this phenomena about how this is how career criminals are born. They commit a crime which is hard the first time, then it gets easier and easier to do, to the point where they don't care and it is second nature.
Thinking along those lines I wonder if past relationships can contribute to creating women who serial cross their man's boundaries.
Anyway, since that is not an option for you, you will not find any other advice in the PU realm to help you. PU teaches set the boundaries, be clear about them, and be willing to move on to the next once they are crossed intentionally by a woman, and make sure that she knows this is the consequence without a shadow of doubt.
You my friend are past that point, and there is no turning back.
But you still have hope. Jack introduced me to a non pick up book called "Thank You For Arguing" that doesn't teach you to "argue" in the conventional sense, but to win people to your side. And not in the spineless, respect-less, dale Carnegie's how to win friends and influence people sort of way.
For now, you need to let this go because it's building resentment in you towards her. Read that book and you will come up with an answer yourself because at the end of the day you want her, and you want her to be on your side.
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"Keep your head up in the sky, you just a baby."
https://www.youtube.com/watch?v=HccL8jUIIWU - Adoration of the Magi Lupe Fiasco