Guy Probs

I started talking to this guy and we talked for a couple months and we were becoming really close, but then out of no where he stopped talking to me. About a month after he texted me again saying he was sorry for not talking to me but he got a girlfriend and she didn't want him to talk to any other girls. So I forgave him and we started talking again  but now he's sends me a couple text and then stops talking to me. I really just want a friend to talk to but he's really pissing me off. What should I do ?