Orcs are Green.

I'm 22 years old, my gal of 9 months is 21.I've been cheated on in pretty much every relationship so obviously I have some trust issues. With her though its been different, From the start I've trusted her. shes extremely blunt, honest n childish . At times it can be painful but It rather the truth! The other day we were on da fone and we shared da passwrds of our mail id, and that nite I sat on my pc, I opened her gmail and to my surprise, i shocked to see some of the chats ! Turns out that she and da other guy have had classes together and "hooked up" over the a sem, while she was far from her home. nd i once saw her naging wid da guy till late 9'0clk at bus stops,I asked her what it meant she said it meant that if she wasn't with me she wouldnt mind "tagging" him . I proceeded to say fine don't let me stop you. Obviously I know that this girly speices is Stubborn by nature. BUT to let one know your still interested but the fact your in a relationship (which i never pressured her to get into with me) is the only reason stopping you is way over the line in my opinion. I think its wrong on many elements and really makes me wonder why "we're even together". She said it was just innocent flirting and seems sort of "SORRY"; only after the fact she could tell I wanted to break up with her. I can't stop thinking about it and it really makes me feel like I lost some trust in her. She didn't actually cheated me, but that whole thing really bothers me. she told me I'm crazy, and to stop worrying because she'd never cheat on me. Aside from this, whenever I bring it up she gets extremely mad that I opened that "SAVED CHATS " . She said that I display "psychotic tendencies" so shes "scared down the road" i could be a psycho. Whatever. Alright so it was wrong for me to click on those chats, I've told her this and I understand. Psycho? I just dont get it? Also, she has left her mobile with me before, I never once felt the urge to go through any one of those msgs. I had every chance but I had no reason to. I trust(ed) her. I don't really know if I feel the email thing was a violation of privacy ???? because even shez was very close with me. I feel I'm so far from a snoop...I think most any other boys in my situation would have gone through her stuff at all these other times. I'm still considering breaking it off because I'm just nervous this is the first step towards infidelity. I don't deserve to go through that again. The fact that she not only chats with other guys but has made it known to at least one boy bothers me. So, Am I overreacting? Do you feel l violated her privacy or is she just trying to make the problem seem like my fault?!