I Need Friend help please????!!?

Ok, so my friend likes and is going out with this guy that is really wrong for her, just not her type(the lying, cheating, not caring kind that just pisses me off!!) And I am trying to tell her that his a lying, stupid person..and she is deluding herself in to thinking that he's perfect and would never do anything like that..They don't even Talk!! They just stand in the corner in awkward silence-I'm ready to murder him!! What should I do to get the message through??