I would suggest reading my blog from about the beginning of December 2010 until now (March 2011)... It is filled with the result of staying with someone who is mono.
Other than that there is a world of good stuff on here to read. The blog section is a good place to read others stories... do a tag search on "mono/poly" and start reading. Maybe it will become more clear what to chose if you do so.
Have you told her that you intend to decide? You have a very well laid out OP. It seems you have thought of this situation a lot and realize it comes down to a choice of the two. Perhaps if she knew this she would be able to do her own searching and educating and realize that there is some budge room for her... especially if she knows she has a 50/50 chance of losing you... maybe if she did lose you she would find a way to move her boundaries... not that you should use dumping her as a way to move forward, but when presented with facts, it might help.
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