Did you have an idea that marriage would mean the end of poly? Did you hope that you would become her primary and therefore have more say in what she does? Primary does not equate that, but some people assume that.
Are you both trying to make a point to each other somehow? That she really loves you because she committing? That you are a better man than anyone else?
There seems to be something a miss here. Maybe not. I could be completely wrong. Hopefully you'll get to the bottom of it, if there is, before getting married. Marriage does not make these things go away.
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