Did you try doing a search for NRE? It is in the tags in the search engine.
My friend wrote tonight in another place I talk about poly about accepting ones partner as human. They are just living and loving as best they can and doing their best to accommodate and do right but us. Its hard to remember that though and to trust them.
It sounds like you are no longer in an open relationship as she has fallen in love. Well, it happens. It happens a lot. Sex can do that. It brings people together and creates strong bonds. I believe more often than this time in culture allows us to believe.
The good news is that NRE runs out eventually, the bad news is that you will likely have to live with your partners "teenager" mentality. No offense to teens... but hopefully that makes sense.
It sounds like you are communicating, giving them their space, changing old boundaries that no longer work and have morphed into something new. That is really all you can do.
Make sure that you are clear what will help you feel safe and secure and loved to your boundaries... time management can do a lot in that department along with making sure that there is respect around them contacting each other while you are having your time together.
Spending time all three of you might help also. Not sexually, but to get to know what the dynamic is with the three of you and to discuss boundaries together.
There are some really good threads for those starting out if you do a tag search for "lessons" and "foundations" too.
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