That does not mean, that if you think she is too young that you need to hide that opinion, but present it in a way that acknowledges her ability to make different decisions, and make sure it conveys your concerns about the effects her choices may have on her rather than an issue of right or wrong.When adults approached me in this way when I was a teen, they made the most impact.I will speak from my experience as a troubled teen.The most important thing you can do (and obviously already are) is to be involved, and concerned.As for the rules themselves, I think that the rules we set for teenagers are a safety net, not a protective coating, the kids can get around them if they are determined.Set the rules that you think are appropriate for her, if they are not 100% enforceable acknowledge this to her, and be clear about the consequences if you do find out that they have been broken.If you could, you might want to have a goal of get teen to stop having sex.But you seem equally convinced that this is not achievable.
They have to be based on something else, giving her reasonable guidelines within which to learn to take responsibility for herself.
(There's a chance that he's a friend of a friend of a friend!
My mother-bear self wants to lay down the law and tell her no way in hell is she going to be dating an 18 year old who we know nothing about.
I am only speaking from experience my daughter, found herself pregnant at 14 and although it brought us closer together emotionally, it was not a pleasant experience.
She is now 18, more mature and a fabulous person, looking back she says I was just a kid - what did I know that something like that would happen to me. I have a 16 year old daughter, though she is pretty easy, but I was a troubled 16 year old once (and I have also transracially adopted a child with challenges).