I've mentioned in another thread that I'm both new to the forum and new to a poly community like this, but I've been living a poly life for 2+ years and done a lot of reading and research. So take this for what it's worth considering the source.
I've read back through some of your older threads. One thing that I am seeing as a theme in what you write is this; you are somewhat hung up on what people "can" or "can't" do, or what is "in line" with what you think poly is or should be, or what you think others should feel or have (like you wanting your g/f to experience a certain kind of relationship either now with your husband or later in her own life and family ).
I don't think you mean it in a bad way at all ... I suspect you're still clarifying a lot of things in your own mind, as you've said you're new to poly and you wouldn't be here if it weren't for the people you love.
So I guess my point is ... does it really matter if these folks on this website call themselves husbands and wives (multiple)? Does it matter if some people have V relationships (like I do), or partial triads (like you and your husband and your g/f), or any other configuration of poly?
I wonder if you're not looking for some kind of rules or labels or something to fit things into to make yourself comfortable with the relationship you're in?
But one of the things I've learned is that because these are relationships out of society's "norm", there is no one right way to be poly. If you want to call your significant other your g/f, great. If you and your husband want to call her a 2nd wife, why not? Some people might refer to her as your second. Other people don't like that term, feeling it's marginalizing her role. Some people have rules in place where everyone HAS to relate to everyone else or the relationship isn't allowed. Others want little to no contact between the top points of the V. Some people have closed groups, others have open groups.
There are a lot of differnt flavors and styles of poly - and none of them are any more right or wrong than any other, as long as all the members agree.