I agree totally with @choreplay and @worriedguy….on the one hand, it looks like you missed out on a honorable guy. On the other hand, you have to commend him as he did do the honorable thing.
I remember when I was fresh-faced and in my freshman year of college (I was also 18) and I fell into a conversation with a teaching assistant who sat next to me on a bench in one of my first days at university. He was definitely on the prowl, and I was as naive as could be. I thought he was just a “nice guy” looking for a friend. I was impressed that he was working on his Phd and blah blah blah girl-from-smalltown blah blah. He invited me to “his place” and I was silly enough to think that he was just being hospitable and attempting to make me feel less homesick. Instead, he was just looking for someone fitting my profile (naive, away from home, etc) to seduce.
Let me just say that I managed to extricate myself from a possibly dangerous situation by simply saying that if he did not take me home immediately, I was going to report him to the university. But I remember when I was saying it (as he started groping me) I felt like I had actually asked for this by accepting his invitation. I mean, it was, after all in the middle of the afternoon, what could happen, right? (Right.) And honestly, coming from a small town where people really were friends and friendly I thought we were going to just be friends and have a cup of coffee. I grew up a lot that afternoon. And frankly, I remember being completely grossed out and feeling violated and betrayed (betrayed by my own naivete, too, mind you.)
Please don’t take this personally. It wasn’t meant that way. It was just the reaction of a decent guy who was attempting to protect you and protect himself. And frankly, after my experience (and having lived quite a few years after that incident of my youth) it is actually a very noble act on his part.