@MinionKevin
Your dd sounds like my elder dd.
She is summer born and (imo) is nd.
Wouldn't leave me, either for sleepovers, trips etc
She's always - eventually - found her "tribe" and has groups of lovely friends from 6th form and uni who accept her for who she is.
She's currently away with uni friends and they are doing things like escape rooms, pub quizzes and bike rides :)
None of them are party kids and they are all quite "nerdy" (I mean that in the best possible way. I'm a nerd, too!)
I think leaving secondary and getting to a bigger pool of potential friends and more diverse people is key.
I hope its the same for your dd x