Do you actually like any of the people in the group? Or is it a group that you've just ended up in a new place and then stick with for a social life?
If the answer, is, 'no not really' then back away. It doens't have to be dramatic, just ease up on the meet ups and don't be too quick to say yes. Then use the time gained to experiment with classes/hobbies etc to try and build up some genuine friends. This can take some time, but it does work. Maybe also book in some visits to the friends who live further way to boost you in the meantime.
If you genuinely like any of them individually and - choose carefully here, avoid flakey inconsistent people - then try and build the one on one relationships and worry less about the group. Again, patience might be needed, it takes time to make an old friend.
I do hear you. I struggled in adolesence, fared better at uni and later on, but those early teen years left a strong imprint. I was particularly sensitive about group dynamics, but at the same time too ready to attach myself to groups just to have a sense of belonging to something.
It's also quite hard in your 20s in some ways. It can feel like people expect you to be off living your best life with your gang, but if you're in a new place, friends are dispersed, plus some settling down/other not yet, it's not always that straightforward.
Give your younger self a hug and reassure her, think carefully about this group (as above), be ready to experiment with new hobbies/meet-ups, and make peace with the worst case scenario. So, think about what your main worry is of not being in the group. E.g. weekends with no plans and feeling lonely, what else can you do with the time? If you can tackle that you'll be less inclined to hang onto a group that isn't good for you.
Good luck!