The fact that your "friend" chose to slam you in her internet diary rather than talk to you directly indicates that she is really a coward, much the same as my ex friend was.
I'm not sure that I agree with this statement. In fact, I don't agree with it at all. I'm sure in some cases it could be true, but I think it's assumptive.
I have actually been on the other side of this kind of situation where I wrote about a friend in my blog, rather than talking to her. It wasn't a PA way to get a message to her (she had long since stopped checking my blogs), it was a way for me to work through my own troubles and feelings regarding our failing relationship
I think best when I write, and I communicate much more clearly then as well. In fact, I often write about my problems and things I am experiencing before I will talk to friends about any of it, because it takes my writing about it for me to get a clear understanding of why I am feeling the way that I am. So often, I will write a blog and my friends will read it and then call me to talk more about what I have written, knowing it's hard for me to put things into words verbally (which is ironic given how much I talk!).
I don't really write with an audience in mind though if I know that I have written something that will upset someone who reads my blogs I will set that entry to private. But writing my blogs is, to me, the BEST way for me to communicate emotional things to my friends. They are mostly emotional things I am dealing with, independent of any of my friends, but not always.
In any case, I wrote about the friend I wrote about for 2 reasons. The first being, it was what I needed to do to sort through my emotions. The second reason was that due to her actions in the preceeding months, I did not feel like I could talk to her about any of it, and I needed to get it off of my chest.
I'm sure, when she eventually found out I had posted what I was feeling in my blog she was hurt, but it was her actions that caused me to feel like I could not take this to her directly. I am not saying this was true in your case, but I'm sure my ex friend wouldn't think it is true in her case either.