The fact that bullying messages are posted on social netwrok sites can be used as easy evidence against bullies. Just remember how it was before all the electronic stuff wass available. The bullies met you somewhere and threatened you. And you had nothing to prove that he was threatening you. Nowadays you just pulls out message from your phone, e-mail, or whatever way was used and goes after bully. The problem is how it will be handled. Usually reporting bullies will backfire at you. So you should be prepared for that.
Just one question. How did 14 year old get drunk in the first place?