The type they practice aligns with the definition of the primary + others. I gained some insight from them, but they told me that their prefered method is, as I have learned, one of many possible ways of practicing NMR. They also made a point to tell me that their community does not easily discuss NMR due to fear of sociocultural biases and prejudices they have experienced.
Welcome!
I've been to therapy (not for my NMR but for anxiety) and one of the things that helped me was, I'm so used to adding a disclaimer of "I know it's oout of the norm", "i know it's weird" etc that I did when we were in the "getting to know you" stage. The first thing she did when I added the disclaimer was challenge it. She said "Why is it weird?" She was gentle (which is great for me because while I like people being to the point, being blunt makes me feel backed into a corner); but by her asking me how is it weird or out of the norm...all I could do was be like "well, society has deemed it unacceptable...", and to that she answered "I know that makes it harder to come out, and harder to deal with the sociopolitical, etc aspects...but is it weird for you?" I had to say it wasn't, because it's true. By forcing me to remove the disclaimer, it made me feel like she felt my relations are valid. That any time they came up in any context, she wouldn't act weird about them. It built up a lot of trust very quickly.
As well as learning both their names. Not having to constantly clarify was so nice.
Also, acknowledging and understanding the other aspects of NRM is super important. The legal side for family law and how it affects people with kids, the fact you cannot be legally married to two people (but where I am, your first cousin is okay...), or even technically in a romantic relationship with two or more people, and how, when your love is considered not only not valid, but a crime...that's scary. That means, if anything goes wrong (again, a separation with family law, or ex spouses wanting custody when they shouldn't, or...even a not legally binding marriage being considered law breaking by the government [as is where I live]) means that coming out to family. friends, work, not only has that layer of difficulty about being accepted but actually being in legal trouble depending on who you come out to.
So not only do you experience frustration over not being able to take both spouses to work functions, or family functions (even if they do come, sometimes you have to deflect or be like "nah they're a roommate") but there is a genuine, valid, fear behind it. Job loss, child loss, fines...all are possible.
My experience with people being prejudice is:
My mother-I'm not out to her. I tried to breech the subject by talking about polyamory and how I believe it is valid, as the discussion continued I asked "how would you feel if I was poly?" she said she'd be dissapointed in me [from a parent, a very upsetting thing] and that she'd slit Z's tires. So, that really made things a no go. Am I afraid she'd actually slit his tires, no. Do I think she'd disown me, no. DO I know it would lead to emotional abuse; yes. So, I just continue to let her believe that he is a roommate that I love dearly who will live with us forever. I have even said that when our current cats die, we'd get a cat together. If she isn't gandering on, I'm not helping her.
My father-He'd honestly probably be chill with it, confused by the dynamic, but just want me to be happy. But, same issue with my MIl [below], keeping stuff from his wife isn't fair. As he already knows I'm bi and has hid that.
My MIL- She'd be okay with it. But, we are not okay with forcing her to keep it a secret from my mother. She wants to maintain a positive relationship with my mom. And forcing someone else to bear our secret is not fair to her. So, same deal with my mom. If she doesn't guess, we aren't telling.
My boss-He'd be awkward about it, and because I'm a contractor he can toss me for any reason he wants. I need to pay my mortgage. It's easy to not tell him as we don't talk much.
My coworkers know, my facebook friends...well I don't exactly play on the DL on facebook. But, if they don't understand it they will accidentally invalidate my anger over things and fears over things. The most recent was "if you can't change it why worry about it?" Well, it's not a fear of worrying about what MAY happen, it's a worry about what happens daily to people like me, and the fact that, with one slip up things can get bad.
Also, a helpful thing would be understanding that even relationships in tandem have different dynamics so to speak. No person is the same so no relationship is the same.
Thank YOU for asking!