Friend of a friend gives me bad vibes… but I don’t know how to feel about it.

I have a friend who has a friend group and I want to say that we’re all pretty close. About 9 of us and we’re all in our 20’s. We have a group chat where we all talk every few days and game on the weekends. The person who runs the group met someone and invited them to the group too but from the get go they were kinda snappy and rude. I wanted to stay amicable though because this person ( ill call them person A) is close to my friend (call them friend B). I love everyone else in the group, they have been wonderful and have helped me through tough times. I know person A has also helped friend B similarly so they’re super close I guess, but when I would talk to them they just felt off. They are kinda what people call abrasive. Very loud personality, cut and dry, but capable of being kind to Friend B so they have developed a bond. When we first met, they snapped at me because I didn’t know how to do something until someone told them I was new to the game. Then, usually, when I tell friend B about plans I have they are super supportive and kind, but one day I said something about a restaurant I enjoyed and Person A just went in to how I could have picked better and Friend B went along with it too. They also like to really pick on my age, I’m 25, and they are 20, the youngest in the group. They also do it to Friend C and D who are 26 and 27. I know it kinda off puts at least friend D. I don’t know. There was also an incident where the shyest person in the group made a dad joke, which is something we do often as we’re all friends and we all usually just groan and roll our eyes, but Person A just went at it about how Person D is “actually not funny” and what an awful joke it was with a dry tone. I just think that if I barely know you, you wouldn’t behave or act like that off the bat? Ever since, there will be interactions where I don’t really like being around them or even hearing them speak. I know they’re so important to friend B but I just can’t find a way to like them. I feel like it’s not justified. Sometimes it’s fine and they’re FINE, but lately they have been hanging around the group more and I feel like everyone else is getting along or at least not showing any unease the way I do. Even if I’m older, I have a lot of anxiety issues and in my mind, I keep thinking they’re just going to tear me down sometime again. I did confess to Friend E and C about it and friend C was there when the joke incident with friend D and Person A happened so they kinda understood and they even stood up for Friend D then but I don’t know if I should bring it up to Friend B about it. Because they really like Person A. I only told friend È I was uneasy but I told Friend C the whole of it and Friend D is actually a longtime friend so they knew from the start I felt this way but it’s weighing so heavy on me that I get heat flashes when they’re around me and I can’t enjoy games or chats when they’re around. I believe my chronic nightmares have to do with the stress of this too. It started since they started coming around more. I only dislike a handful of people in real life, I want to say I usually get along easily with people but this one is tough. I kinda hinted at this earl on a year ago to Friend B but they just said that person A has “been through it” and just isn’t a sunny person. I feel like person a doesn’t act like this to anyone else but me and friend D. I’ve been holding this in for a year.. I just don’t know if I should tell Friend B. It’s kinda hard for her to build genuine bonds and to be fair, Person A does match them very well.

It feels nice to throw this out here though. Thank you if you read this far :)