Confused About a Guy

I have this guy friend and we have known each other for like most of our lives, we're good friends. I have always thought that we had a connection. Like, we flirt sometimes. One time, he texted me when i had a boyfriend and he texted me, saying he liked me and stuff, but I thought he was kidding because he jokes around but he told me he was serious and I didnt believe him.

Now that I am single, he isn't. One night we were at a friend's and everyone was drinking, he was a little, but wasn't wasted and he told me that he likes me a lot and always has, but he has a girlfriend so I don't know what to do. He told me this about two weeks ago and we haven't talked since? Should I mention it to him? HELP!

How to really get to know the person you are dating before making a big commitment