I brought up the possibility of us parting ways while they figure it out. I wish I had known early on that this was going to happen and his girlfriend had so many uncertainties about poly. I would have avoided letting my heart get so involved.
Sounds like this is what you want. So tell him that's what you want most, so you can move yourself to a healing space. You feel yucky right now, but taking action to move towards less yucky is not a bad thing.
Everyone is responsible for their own emotional baggage. You tend to you and what you need to feel less yucky.
In some ways I feel bad that I have brought so many difficulties into their relationship. I am very fond of his primary girlfriend and consider her a friend in her own right, and I want nothing to do with hurting her.
Her lack of honesty brought this -- not you. You were operating in good faith, as was the BF. She was the one who lied about her comfort level and willingness to be in a poly configuration. "Just told him what he wanted to hear" for YEARS?!
If I were him I'd be pissed off!
Does anyone have ideas on how I should proceed?
Could tell him you want to take a break so they can sort themselves out and to look you up if they do (if you are still willing then.) Then could date other people once you are in a healthier headspace.
You might meet someone more compatible, you might get back together. You cannot predict that.
But the point is that YOU are opening yourself up to your next future happiness with whoever that might be and not stuck in "limbo" where your fate is being determined by other people. Do not give you power away like that. YOU are the captain of your own ship.
Should I keep waiting for his primary to become comfortable with our relationship and poly in general, even if it takes a long time?
So basically put your own life on hold? And your next future happiness on hold? For a dishonest/fearful person to learn to be honest/not fearful and then MAYBE decide on poly so that MAYBE you can be with the shared sweetie? If it were me? That's a lot of "maybe" to me at too high a price tag -- my whole life on hold? No, thank you.
I'd part ways, date, and tell them to look me up if things sort out in a relatively short time. Then if you are still willing you could reassess. And if not willing or if it never comes to be -- you haven't been sitting in limbo yuckies all that while.
He's been in a relationship with a lying primary partner for years.
You have been in a relationship with a lying metamour for 6 mos. You got off easier! Step away from messy and move toward your own better healths.
Is there anything I can do to help make her more comfortable with it myself?
You cannot make a person feel anything.
You could bow out to give them the space they need and give you room to open to next future happiness.
You could point them to resources:
You could encourage her to be more honest in relationship. Stop operating out of fear-based stuff and move toward reaching out for her own next future happiness.
An aside... There is NOTHING wrong with monogamy! If it isn't with this guy -- so what?
Feel yuckies for a while with a break up and then feel better and then move ON to the next future happiness. It is just sad that she's been in relationship with him for years in a relationship model she does not seem to care for naturally, doesn't seem to want to work on learning, and doesn't seem to want to end because of.... her fears. This is not her caring for her mental health, emotional health, or spiritual health very well.
I don't think these are bad people but they don't sound like especially emotionally strong people right now. You don't mess with fragile.
As a secondary, what sort of rights do I have in this situation- I feel left in the dust at the moment- he is fighting hard to keep what we have, but the decision is out of my hands, which is a feeling I am not fond of.
If you choose to stay here, it is YOU choosing to stay here. It is NOT "the decision is out of my hands." You don't like how it feels? Change your behavior then. See if you feel better.
Could read more about secondaries:
Could choose to leave and give them (and you!) some space. Esp since you feel frustrated that they are only now working through these issues.
If you DO choose to stay here, you have the right to ask your shared sweetie not to overburden you with his problems from his other relationship. You could examine yourself inside and figure out exactly where your willingness and limits are on staying-ness and also how willing you are to work with a weak metamour.
But me? Honesty is a foundation for partnered relationship. This person has not been honest with herself and him for years. That's not sounding great to me, and since this is early days at 6 mos in -- it's not like you have oodles invested here. Time, emotion -- but nothing you can't change and you already indicated your preferences for cooling things off a bit.
So... I'd go with that. Cool it off, give them space to deal with themselves, and you look out for your best healths.
Whatever you choose is ultimately up to you. I am sorry you are dealing with all this rigamarole. You did act in good faith -- it isn't that you did anything bad. Sigh. *hugs*