So, I have been talking to this guy for about a month and I've known him for about a year. I haven't really hung out with him yet, but my question is how can you tell someone likes you, through an online relationship?

You can't, you can't tell for sure if he is married, or anything just online.

The amount of men and women who find online affairs are large.
Now you can find people on line, I meet my wife on line about 9 years ago

But honestly how do you tell if the guy you meet at the bar or the guy that asks you out at work likes you or just wants a fun time. You don't until you get to know them more.

Only thing I will say is sk him about his sincerity about you relationship, get to know each other more, and then if everything is OK and there isn't too much distance between you guys maybe pursue a relationship... remember be careful because there are a lot of sick-o's out here.

I've met 2 in life that I met online... the 1st one is now one of my best friends, we thought we REALLY liked each other but we went out and realized we were better friends, the second guy is someone who I am in love with. So id def say if you think its serouis meet him. Again Be Safe because people on the internet lie!