Hi,
So a bit of background, DD is likely on the autistic spectrum, but doesn't have a diagnosis and was never officially assessed. She was seen by a SALT when she was about 4, but I was told that all was fine and if anything, she was a little bit ahead. She was also assessed for dyspraxia as she can't ride a bike or swim and used to have a real issue with stairs, but again, the assessor thought all was fine and it was to do with her core strength.
She always had mammoth tantrums at home and at pre school, but by year 2, she controlled her behaviour at school, but not at home. She struggled a lot, socially. Just couldn't seem to keep a friendship going and very sadly, never really made any friends in primary - apart from the occasional, short lived one here and there. Academically, all was fine. She's an
incredible artist and writer, but still, life was tough during those years.
She started high school and.....then there was light 
She found "her people". A group of mainly girls, who are from all different kinds of backgrounds. Some are very similar to DD, some just like DD. She finally had a group of friends and she blossomed.
However, because she didn't have friends until now, she's not really had much practice with her independence and she's way behind and as a mother, so am I, because I never had the opportunity to give her more freedoms iyswim. She never did the walking to a friends house or walking into town with friends etc. I tried to give her things to do to gain her independence, like go to the shop on her own and get a small amount of shopping, but she would always freak out and need help.
Anyway, now she has this group of friends, she wants to jump straight into the deep end and doesn't understand why, for example, I can't just let her into town for the whole day. She should be at her age. Of course she should, but she's still very immature for her age and she is naive and she lies very easily. It's something we've really tried hard to stamp out and I think it's got slightly better recently, but I have to be able to trust her. Well, more than I do right now.
I know I need to start letting go, but honestly, how can I do this when she appears so disorganised and naive.
I'm genuinely looking for advice. I really don't need flaming. I have tried so many things and honestly, this is the short version, but bottom line is, things can't go on like this. She needs more freedom.
Any advice would be hugely appreciated.
Thank you.