Is it normal to like someone online and then hate them when you see them?

At my school there is a boy who is albino. I can spend hours online talking to him, and he's a really good friend of mine. I just can't seem to talk to him when we're at school. I don't know if it's because i tell him a lot of personal things about me (like what my fears are, and if im having arguments at home etc). I just really can't stand him when i see him in person. I don't think it's because im shallow, although he's not like the rest of my friends. My best friend doenst like him, but that's because she went out with his best friend and he gave her a lot of stick for it when they broke up, so maybe that influences me? He's a nice guy, but i just can't seem to get on with him in person. He really annoys me - especially his voice. Maybe i only like him online as he's like a diary - someone i can spill my feelings out onto, without thinking he's a real person. Should i stop talking to him online? Or make an effort to talk to him at school (i've tried before and just felt really uncomfortable and awkward, coming away with the feeling that i should stop talking to him online)? Or remain as I am?