Okay well, how can you expect to have a relationship with her if you can't start a conversation with her mate? Conversation is the key to all relationships!
It's really good that you talk on the computer and stuff, so it shows she does like you and is willing to talk to you, but you need to realise you can't just make yourself someones best friend and expect to go out with them, it isn't all on your terms.
I think you should just keep talking to her online and what not, but start just talking to her in school - just like you would on the computer! Start off with a wee 'hiya' when you see her around in school, and gradually build it up into talking about stuff.
If you don't build up the courage to get a conversation going though, I doubt you'll get anywhere with her!
Good luck!
