I’m jealous of my friend’s new friend

I’m (20/f) in a trio friend group with Trina (21/f) and Beck (21/m) (fake names) since the beginning of college (about 7 months). We immediately became friends and are platonic soulmates. (Of course they and I have other friends.)

2 weeks ago I introduced someone (lets call her Tory (20/f)) who was new to college to Trina and Beck. I wanted to be nice since she knew no one and she seemed like a really nice person.

We all spent the day together and it was fun but she‘s not the type of woman that ‚fits in our trio‘. I cant explain that well but it’s just that feeling that I couldn’t trust her and hold a genuine conversation with her w/o feeling like an idiot afterwards because I’m weird and have anxiety.

I was really sick for some days and stayed home…surprisingly, when I came back, Beck, Tory and Trina seemed to have gotten close. Especially Beck.

Whenever we (me+trina+beck) want to do something together he says that Tory will join us w/o asking us first if we’re fine with that. When we are together Beck only talks with Tory and Trina and I talk. This is why it’s been a while since I had a real conversation with Beck.

After such a meeting, Trina and I had to catch the bus while Beck and Tory stayed behind.

I asked her how she feels about Tory and she answered that she was nice and funny. I felt like Trina wasn’t telling the whole truth so I told her that I don’t like how close Beck and Tory have become. As soon as I said so, she told me how she doesn’t see a deep friendship with her and that she also doesn’t like how often Beck and Tory are together.

We’re both jealous and anxious that Beck wants Tory to join our „trio“ or worse, we would stop being friend with him. I felt relieved that I wasn’t the only one but at the same time this made my/our concern more realistic.

We both feel stupid because of our jealousy because we don’t want to habe a weird atmosphere between us and also with Tory. He should be able to have friends outside of the trio but it feels different with Tory (not romantically btw he has a girlfriend and they are lovely together). What are we even supposed to say to him? „Don’t be friends with her because we are jealous.“ is dumb because rationally speaking we can’t suddenly cut her off and I genuinely like Tory as a (good) friend.