Hi, I'd like to help you with your question.
It is easy to feel anxiety about children making a seemingly adult decision. At the age of 14, it is very natural for your daughter to be interested in dating. It is not ok, however, for her to be threatening you with going behind your back and dating anyway.
Your daughter seems to be trying to include you in her decision to date. This is a good thing, showing that your daughter trusts you and is willing to talk with you. She has also come up with a scenario in which you can meet this boy and get to know him. You may want to take her up on her offer. She is trying to keep the lines of communication open and let this boy get to know you as well. The more you know the people in your daughter's life, the better you will be able to know what is going on in her life and be able to protect her.
Invite her boyfriend to have dinner with your family. That way, you can get more than just one opinion on who this boy is and if he is appropriate for your daughter. If you have other children around your daughter's age, they may already know this boy and can offer you a better idea of what he is like when he is not in front of other adults.
Let your daughter know how you feel as well. Tell her that you are afraid that she will get hurt and that you are worried. It is ok if she knows your fears. That way, she'll understand there is a reason behind your caution and you are not just being strict for the heck of it.
If you are comfortable with the situation, let her go out with this boy. But also talk with her about your limits for the relationship. Agree to guidelines you both are comfortable with and make it a give and take. You allow her out to 10 pm with this boy, but she must call you every two hours for example. If you'd like, write it all down so there is no disagreement later.
As she learns the rules and handles herself well, let her have more freedom, but only to the level you feel ok with. Trust and honesty should be the main focus of your agreement.
I hope this has helped you,
I think letting her know how you feel would help. If she knows you are concerned about her and that you are worried she will get into trouble, she will think twice about her actions. I find that when mothers and daughters are close and talk, the daughters are more willing to see the effect of their behavior on not only themselves, but on their parents as well.
You are doing a good job. Keep in mind that you have been the best parent you can be. Now is the time to let go a little and trust in that good parenting. Your daughter is going to have to make her own mistakes to learn, but with your good parenting, she will make the best decisions she can.