There are some good threads on "moving in" and "living together" if you look around. there is a thread called "Mulit-partner co-habitation" too.
In a nut shell however, I think if I were in your situation I would not be calling this a triad, as it isn't one if you are not having a relationship with her other than sharing a partner... she sounds more like a metamour. Fine, but calling it like it is might mean that there is less confusion about responsibility and commitment.
Secondly I would be having her move out. She is not fitting in where she is at and I wouldn't of moved her in in the first place... I am not an advocate for moving lovers in when there has been no process and everyone is in NRE... I just have not seen it work out pretty much ever and hate to see people end up in pain...
As to the PMS thing? Bullshit. What the fuck is that shit? Seriously... talk about creating what he wants out of thin air. He sounds like he is showing off to relatives, being disrespectful and generally being selfish.
Ya, if this were me I would be laying it all out for both of them about how I feel, what I want to see happen and then realizing that I might have to move on myself if there is not a change.
The first move I would think would be to get my finances in order, find a place to stay and figure out what I want and how to say it in as polite and respectful a manner possible, knowing that I might have to put my foot down firmly... Life is too short to fuck around with selfish people who are not willing to consider my feelings.
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