you should be working this out with her too. If she is treating you well, being honest, trusting you, then things are going well in my book. Make sure she she knows your feelings... all of them! keep your self as open as possible. It won't be fair to her if she is being a good poly person, that you suddenly leave to be with another that suits you better. That does not compute in the poly world and she will be very hurt. We do not leave, we morph. Mono's leave. Very different. Does that make sense to you?
Really, you can drop your fear in regards to your cheating ex's, it sounds like this woman is a fabulous poly lady. She is doing it all right so far... the joy of her honesty is that you will never find her cheating. Why should she, she has her freedom, is keeping it honest and upfront with you and you will never be left wondering. This could be the benefit of this relationship if you allow it.
I would suggest doing a lot of reading on here. There is tons of stuff written on your situation. I am sure that some of it will be useful. Do a search for what you are looking for and see what you come up with.
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