I'm not sure if this is the proper place to post this, but here's hoping!
Some context about me that might be relevant and explain why this is something I'm struggling with is that I do have an official diagnosis for both avoidant personality disorder and autism. Both of those together I think tend to make me a lot more introverted, and while I try to recognize when I am being avoidant I know I am far from proficient at it.
To make very long story somewhat short, a long time childhood friend of mine invited me to hang out and play games online with some of their friends that they know irl. It turned out that they were sort of "soft launching" their four way poly relationship and it's.... kinda rough. I get along with two of these people plus the other person in the group who is not at all related to the whole poly thing, but the fourth partner is continually getting more and more on my nerves, and I don't know how I should proceed.
I feel a bit silly because realistically we're all adults ranging from 23-27 (I am the youngest) in this group and I should be able to just say "hey man, this behavior is really starting to bother me, can we try to tone it down a bit?" But seeing as this fourth partner has three people who all really seem to baby them.. I'm not really sure how that'll go.
My reason for being unsure is that this person claims to have like... a lot of problems. (Autism, ocd, bpd, ptsd, cptsd, anxiety disorders, a plethora of autoimmune diseases.) I've no idea which are real and which may be self diagnosed, because all the people in that relationship don't see any issue in self diagnosing and all have equally long lists of illnesses they say they have. (I say that in a doubtful way because two people say they have lupus and a lot of other things that I honestly can't even remember the names of. Normally I try not to doubt people when they say they have something wrong going on in their bodies, but there's just a lot of rare diseases in their lists it feels like.)
The fourth partner is very.. erratic shall we say. They won't communicate when they want to join in and then be upset that the group has to rearrange things to make that possible. They will start getting very upset and it causes everyone else's moods to nosedive if they don't think they're doing good in a game. We play a lot of 'friend slop' stuff because it's very low stress and even then if two people go ahead while they're lagging behind with everyone else, those two people will get told to stop and come back because they're making this person feel bad, while refusing to listen to any advice they get given. Over text conversations they've even had their partners come in to tell people to change the topic when trying to give advice for certain games. And even when you try to cater to them there is a 50/50 chance they leave without saying anything and then go complain at the partner that's in the same house as them to take care of them, and an hour later say some off handed therapy speak excuse for how they act.
They are also very lewd. I can handle a joke here and there, but when I say every message I see from them has to do with something explicit, I'm not joking. Even after me, sort of lightheartedly, saying variations of "I don't need to know about all that/I'll never be the same person I was five minutes ago." (That's not great communication, I know, but I feel really uneasy about confrontation.)
They are also very prone to complaining about how they just don't feel like taking their medications, to the point that their partners will leave to go have 'talks' with them about it. And also talks about how they're suicidal. They're doing partial outpatient treatment apparently but by the sounds of it have refused to do inpatient care, as per their plan. The partner that lives with them has told me about how they'll go to therapy, come home and talk about how they made some big realizations of how to better themself, and then act like they completely forgot about it a few hours later.
I really enjoy hanging out with literally everyone but them because there is always something going on with them, and it will always become everyone else's problem. It makes it very uncomfortable to have this person who is almost in their 30s having everyone catering to them and basically being like "Yeah, that's just how they are! We've got to be delicate with them." while also talking about how they hate when people make others walk on egg shells around them.
I'm really tired of wanting to have fun and hang out and then there being some Big Thing that always happens if they're involved followed by the next day complaining about how they feel like they shouldn't hang out with anyone unless they're in the perfect mood.
I know that logically my options are talk to all of them and explain my irritation, decide to stop hanging out or just deal with it, but I guess I'm just sort of curious if this is actually something worth causing a fuss over or if I'm being insensitive? Or even just.. how I should go about broaching the subject. All of the partners of this person seem to swing between equally frustrated and babying, so it just feels very confusing to me.
All advice is really appreciated, thank you!