Good Evening Pete,
it may be healthy to try and move on. She had broken your trust and wanting to be friends may be your subconscious hope that one day she comes back.
It is going to be difficult to be able to keep a platonic relationship with an ex partner/lover.
When you're able to move on, having halted contact with her may be beneficial should you meet someone else at some point (they would not feel like they will have to share your attention w/ her)