Hey, Mags, you are not the only person here who responded with saying something about this being a D/s situation, but I admit I missed this point.
OP, other than the mention of your gf being a sub, I didn't "get" that there was any more to this dynamic than that could just be a preference of hers. It would make sense if you are the Domme to both of them, as Mags described, because you do seem to be very much wanting control over both of them (even though I think you said your boundaries are not about controlling them), but I don't know enough about D/s to offer feedback on that. I did notice a bit of a... hmm, not sure how to word this... for lack of a better term, at first I thought it was a bit of condescension toward your husband that he was unable to control certain tendencies you saw in him and needs to be reigned in somehow, kept in line, disciplined. I guess Mags calling that "parental" makes more sense if you are all operating within a D/s dynamic, with you as the Domme.
If it is the case that this is a D/s thing (and I'm still not sure it is, or whether that is 24/7 or in the bedroom only), since you didn't come right out and say it, maybe that's why some responses (including mine) seemed overly critical or off the mark to you. But if it is, I find this rather confusing:
Originally Posted by ChloeJane
My husband is boundary-less on his own. His sexual energy is potent as fuck and he loves women immensely. She is a sub, and adores having her boundaries pushed; it makes it a lot of fun to be her lover, as being creative enough to titillate her crazy intelligence takes planning and work, which can heighten the anticipation of us all seeing each other SO deliciously. Knowing that she is boundary-less, and my husband is boundary-less, we (my husband and I) talked a lot about what had gone "wrong" in previous forays into polyamory and co-created boundaries together.
... My husbands pushiness has the capacity to ruin it, and he needs to watch that desire to get what he wants over the collective happiness - especially when dealing with a highly sexual sub who's truly GGG. I don't want to become his "keeper" or control him, so he has to be extra emotionally responsible in a very salacious, tempting situation. In this version of the story, it's totally ADAM who would bite the muthf'in apple.