Throwaway account but I've had something on my mind that won't leave and I'm trying to find the right time/way to bring this up.

Short version: I'm in a consensual fem-fem-boy relationship where me and other girlfriend are dating our boyfriend

separelty, we all live under the same roof, other girl (named Emily for sake of post, not her real name) has a LOT of mental health and 'preformance anxiety' issues to the point where it's putting a strain on all of us despite how we try to minimally get involved with each other's business and due to Emily and boyfriend having very clearly different relationship goals (boyfriend wants to have a wife and kids and settle down/in for this kind of family dynamic, emily absolutely does NOT want a formal husband or kids), it genuinely feels like Emily and boyfriend would be better off as good friends rather than romantic partners.

Long version below:

So I (31F) live with my boyfriend (36M). He has another girlfriend (34F) who also lives with us. Let's call her Emily. From my understanding they've been dating for about 10 years or so. Me and boyfriend have been dating for about 3 years. We've always all known about each other (I've known boyfriend for about 8 years now). I moved in maybe 2 years ago? Me and Emily are friends, we have a lot of similar interests.

Emily has a LOT of chronic mental health issues (mostly stemming from trauma in her past which from my understanding is pretty dark and super conserv-religious). She's on meds which help but it's obvious the meds aren't quite getting her down to baseline. Because of this, she has a LOT of emotional outbursts, is SUPER hard on herself. She also came into the relationship with already 2 other boyfriends (I think the number now is 5-6, including our shared boyfriend? 2 of them are long distance and only see each other in person when they happen to be in the area). She's also had the unfortunate habit of staying for the sake of convience in relationships (Emily has admitted this herself with past/ex boyfriends) and just uncomfortable situations where her brain finds comfort in the reptition and what's "normal/ expected".

Now the two have helped each other out a lot over the years, absolutely. However, it also feels like they've also genuinely outgrown each other. My boyfriend has made it clear that he's at a point in his life where he wants to genuinely settle into family life, have a wife (formally recognized by gov and everything), have kids, that whole thing. She doesn't. At all. Emily has an appointment to get her tubes ties to help reduce the risk of "accidental oops/kids" to almost zero, boyfriend is fine with this because he understands that she really doesn't want kids and kids also put her body at a medical risk (the two reasons are mutually exclusive and don't impact the other from Emily's words).

I'm fine with that decision but it also feels like they want two genuinely different things out of life. I love Emily platonically but it really feels like Emily and our boyfriend would be best off as friends rather than romantic interests. Emily phrases it that our boyfriend basically "saved her" from a horrible life and he really helped her come out of her shell, realize her interests (sexual or otherwise), etc.

I'm doing my best to stay out of their own affairs but at the same time we all live under the same roof and we all share a bed (boyfriend in the middle of Emily and myself and he takes turns cuddling). Emily is much more words of affirmation love language and I'm physical touch. Boyfriend does his best to accomodate both of our own individual needs and interests. I can see Emily's emotional turmoil clearly stressing out our boyfriend despite how he tries to not let it be known that it's bothering him (I think for sake of keeping peace or try to minimize worry from myself about him? not sure).

Bdsm/sex stuff below

My boyfriend has a consensual BDSM dynamic with myself and with Emily. They are more of a typical Master- submissive and me and him are more of a Dominant-submissive dynamic. There's times when we all 3 have had sex with each other and other times he will have one-on-one time with Emily or myself (for sake of clarity I'm somewhere in the asexual community, boyfriend is straight. Emily is bisexual, I have no issues with doing sex stuff because it's just another means for that dopamine hit, girls are also just pretty, lol).

We're all on the same page with this and try to accomodate each other's sex drive. Emily tends to get overwhelmed easily and stressed out which has done a number on her libido to the point where she and boyfriend have had not a lot of one-on-one time and from my understanding, it's often ended in Emily in tears because she gets in her own head, stresses herself out, and feels like "she let down herself and boyfriend". We've both reassured her constantly that "hey, this isn't supposed to be a stressful point, you've not upset us, made us angry, or anything like that" but she still puts so much pressure on herself I guess "to preform" despite how me and boyfriend have constantly verbally reassured her "hey if you wanna do this, great, we'll do it, otherwise, don't worry about it" to the point where I can see that when boyfriend and Emily try to have some 'sexy one on one time' it's start to take a toll there too. Boyfriend is doing his damnest/hardest to accomodate and help her out, reassure, etc. but we can only do so much while not being in her own head ourselves to the point where now (like I said) they almost never do one on one time and when they do. Emily is often crying her eyes out because she feels like she somehow disappointed or couldn't "live up" to whatever expectation she put in her own head about how everything "should" be happening (be it a group sex activity or one on one activity).

I don't like seeing her upset and I don't like seeing our boyfriend constantly bending over backwards (psychologically and everything else) to help her feel at ease. I know Emily has a therapist but I have no idea how often they see them and what they discuss during said sessions (not my business cause I'm not her, obvious, lol).