Fortunately I haven't experienced this but I wanted to say that I was touched by your words.
I feel for your lady. I feel for you. She seems to be what you were looking for yet there is one huge rift between you that will either be bridged or not. It sounds like its just too early to tell. I hope that you spend the time (possibly years) it will take to settle into your dynamic and develope the trust it takes to make poly work. I hope you do this before getting married, having babies, becoming in debit etc.
It is possible to have a mono/poly relationship but you will both need to work harder at it than most I would think. I know I do in mine. Ours was a different experience. My husband and I met in a nonmonogamous relationship and married after my girlfriend left us. Now my husband and I are in a poly fi family that includes my OSO another boyfriend we share and his boyfriend.
I had had many mono relationships with men and women that were soulmates. To me soulmates are endless and I have found many when I open my heart and let love in. There is not just one. They were all good for me for different reasons and my love for them has created who I am today. I still love everyone I have ever been in a relationship with. All my relationships in my distant past ended with me feeling unfillfilled and trapped because I can not be monogamous. How different my life would of been if I had been able to bring myself to understand myself and to talk about it. I just thought I was a bad partner and lover. I understand your guilt feelings all to well.
Good luck to you. It seems others here have had more to say and I would suggest to both of you to have a look around these forums for support, understanding and to help you ease your guilt.
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