I found a "friends" blog, she didn't know I found it and I read it, I guess I shouldn't have read it but my reasoning was that it was public thus meant to be read. I found out that she was not really the person she was pretending to be. Now she knows I read the blog. She feels that I violated her. What is your opinion?

If it is on the Internet, it was not meant to be too Private. She may have wanted you to read it, by accident.

Hi,
Public is public.
"Better to never speak and never let it be known what a fool you are, than to open your mouth and prove it." Erronously attributed to Mark Twain.
That should sum it it up!
I can truly say that I am not interested in what was said,or the tone; but take it all with a grain of salt.
Peace,
Clarke

The content of the blog is not important. I guess I am looking for vindication, she is in her 30's and is acting like I broke into her house and read her personal diary. My feeling is that it was a public blog, meant to be read. And now that I know who she really is I am not interested in being her friend at all anyway. Should I respond to her at all with an apology for not telling her I found it or just let it go and move on with my life?

Maybe what she presented about herself was a crock, and you know it?
She just needs to be honest.