I may be way off, or missing the general point....could this be a NRE issue? Either that or that is just how their (your fiancee and his gf) relationship is. 2 months of sleeping with you, and leaving her stranded seems a bit harsh.
Yes, she keeps breaking your rules, and entering your personal space.... im sure id do the same in her position. Seems to me like she's getting the short end of the stick. I'm still new to this, but from what ive learned here, your fiancee should probably make more time for her....