Dd is 17
Her friend has a boyfriend age 21
He lives in another county 40 miles away and is having a party at his house.
My dd only knows 1 person there (her friend)
She needs to travel by 2 x trains and change this evening by herself, never done the journey before.
She will have to stay overnight.
She suffers from anxiety and has not had boyfriend (not sure that's relevant).
Her friend has helpfully told her to go despite my saying no.
Aibu to say no? She has a lot of freedom with people/friends she does know. I just don't like the idea that she knows only 1 person and is along from home.