Really? Do you really want to know what I think?
Well, you are thirteen and you probably don't know what love is yet. It is a relationship that will never go as far as the internet and if you want to have a boyfriend, try one from your school. At your age you shouldn't even be worried about a relationship. You are to young to be worrying about this kind of thing right now.
You should just forget about him and go on with your own life.
Like you said, he could do whatever he wanted and you would never know so what is the point in it anyway? You can do what you want. I would tell him you should just be friends and chat on the internet.