Why doesn't he want a girlfriend?

Okay, so I finally got the courage to ask the guy I like if he likes me. He says he does, but he doesn't want a girlfriend. He says that's what he told everyone else, but I don't know if he's being truthful or not, because the whole conversation was texted. He syas it's partially because of his ex and that he has his reasons, but he won't tell me. I really don't want to press him, but I'd really like to know. This happened over the weekend and this is the first I've seen him since our conversation, but he acted like nothing had happened. I'm so confused about the whole thing. I don't know if I should just give him time or back off or what...