OK, Krusty you have made your decision about tonight. Fair enough.
You keep saying 'it's not her, it's the others I don't trust'....but actually that means you don't trust your DD to be able to say no to drink / drugs / sex / getting in a car with a drunk driver, and you haven't suggested how to spot the beginnings of a sticky situation and dodge the bad consequences.
So how are you going to move on?
Today seems the perfect time to catastrophise explain how little things can lead to big things and life changing things. Teens are known for being bad at not anticipating consequences. So sit down with her, and talk it all through. Get her to really think about it.
Very difficult situation for you - yes, you have rewarded her honesty with a 'punishment' as a PP said. So you are encouraging her to be dishonest. Until you have thrashed everything out so you are satisfied she can see worst-case scenarios coming, she is not trustworthy. But only you can educate her to be trustworthy. And she can't prove she is trustworthy until you give her a chance.
Actually, and I apologise if this sounds harsh, it's not the others who are a problem, it's you not teaching your DD what to be wary of yet that is the problem. You can't guard her every minute until she is 18 and then expect her suddenly to be ok without her minder.
You're so close to being there, though! Maybe a couple of long conversations, meet the friends if you have to (but why not trust her judgement?) and then think about letting her go next time. She might go anyway without telling you.