I just read everything here and first want to say that I feel for you. I haven't ever been in a triad (my vee is triad like, just no sex between the men), but have been in several threesomes and in my experience they are great for what they are, but eventually it becomes evident that the sex will continue more successfully if it is broken up into twosomes and then maybe a threesome again sometime later.
Threesomes are a lot of work for some. The dynamic can be exhausting in that there are so many dynamics at play in terms of sexual needs, emotional needs, pacing is different for one over another, relationship dynamics etc.
This being said, perhaps you are ready to break up the threesome sex for awhile and move into some twosome stuff for a bit. The disconnect from your husband sexually is a bit of a red flag for me. It wouldn't be so bad, but if he is getting his needs met else where and you are not getting his one on one attention any more then that is cause to be wary to me. Her
Her attention is also necessary for a triad to work, so one on one time with her is important too. I'm not just talking sexually, but dates, alone time at home, walks, bowling, what ever it is you both enjoy doing together... sex can often come from simply hanging out and feeling a connection when you do mundane stuff. Your husband might kick it up a notch in this way also.
It might be that the relationship status you have is turning into a vee rather than a triad. No biggy really, that happens more often than not. Perhaps being sexual with her is turning into something that isn't as important as it once was. Maybe not to you, but to her. That might be worth checking.
It sounds like you all have come to a place where your relationship is hitting a crossroads and the plateau you were on is turning into a hill to climb. Soon it may even be a mountain. That is how relationships go no? At least they do in my life. Maybe it's time to "fight" in terms of talking about some heavy shit. Maybe not while you are in the midst of a threesome, but a night of herbal tea and discussion. It sounds like you have an email on the go, perhaps you could add to your email that you would like to sit and organize things differently, discuss boundaries and get to the bottom of this so it works better FOR YOU. They get to come to the table with how it might work better for them and all can be looked at and some ideas on how to move forward presented.
You might want to make a list of points to cover so as to not lose your train of thought. It could take some time. This kind of talk can take time to settle in... no big decisions need to be made in one night. Leaving things for later so as to mull over them is totally reasonable. Relationships are made over time and work... not in one moment. It's the journey as much as the destination.
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