<human>: I have been dating my girlfriend since last January and thing shave always been great. She is a sweet girl, a little shy and reserved, but can be outgoing in the right situations. Yesterday I was hanging out in her room while she took a shower and I decided to watch TV. She's an orderly person so she keeps it in the drawer of her nightstand. When I opened it, I saw a black book in there. I thought it was her drawing journal, since she loves to draw, but when I opened it, I realized it was her diary, starting back to three months before we started dating.

She has written in it a lot, nearly five or six updates per week and there are extra lose sheets of her thoughts in there. However, she began mentioning this boy named Garret starting in her entries November 26th, 2013. I was really confused. She talked about "how stunningly handsome he is" and how she is "jealous he has a girlfriend." Se went to talk about a time they hung out during the weekend. The very weekend she told me she was visiting her grandma a few hours away. She said she "enjoyed Garret's full nice lips" and said it was a "nice change from [my] cold chapped lips." I was pretty hurt.

Her most recent entry from Monday talks about how she hopes to break up with me at this carnival we are going to on Saturday. And "after I do that, Garret is going to meet me at the Ferris wheel". But on a lose sheet of paper dated Tueday, she wrote about how she could not believe she could be so rude. She wasn't sure she could break my heart because I was so sweet, but she couldn't put the fire out on her dying affection for Garret's sturdy person.

First off, I KNOW I shouldn't have read it, but now I'm not sure what to do. Do I break up with her first for mutual differences or tell her I know about Garret? Confess to reading the diary? She hasn't even been acting at different since this Garret guy has come into her life.

Condense the text into a few key points
<bot>: read girlfriends diary, she is interested in another guy and planning on breaking up with me, but writes of conflicting feelings saying she doesn't want to, not sure what to do.