Yikes! Declaring you as his Girlfriend, dropping the L bomb in txt msgs, and telling all of his friends about you after meeting eachother twice are HUGE red flags! That is either love bombing or mentally unstable unhealthy behaviour, and the fact that he is 15yrs older than you & doing this he clearly isn’t just being an excited teenager, glad you can see it’s not good and are trusting your gut with this one!!
Yes absolutely tell him via text, he seems to think telling you you’re in a relationship via text is acceptable so communicate with him in his preferred method.
You can be polite, but still be totally straight up & direct with him, don’t dance around it, don’t say any maybes or offer to get to know him more. and don’t let him guilt you into meeting again as he sounds very emotionally manipulative/unhealthy.
How old is he out of interest? And how old are you & your friends?
Just say something alomg the lines of...
Hi Ben, although it was nice to meet you, I am not wanting to take things any further.
You seem like a nice guy, but you’re just not right for me. I don’t feel any connection or attraction to you, you’re just not my type, which is fine as we all have different things that we are looking for in a potential partner don’t we :)
I like to be sensible & take things slow when I’m getting to know somebody. It has to be properly in person over a good length of time before I’m deciding whether or not I’m wanting a relationship with them or developing strong feelings such as love before I properly know somebody.
And I would always expect deciding to be someones girlfriend would be a mutual conversation in person after a decent amount of time, at least several months, rather than just being told that’s what I was am via text after just 1 meet up whilst drinking & 1 date with somebody. We all like to approach dating differently & that’s fine, there will be other ladies out there who I’m sure would be very flattered, but it’s not for me.
Take care, maybe see you around!
Give us an update on what you decide to say & his reaction. Don’t let your friends guilt you into anything either. If they try to push it and make you feel uncomfortable then they aren’t real friends xx