<human>: Condense the text into a few key points

Long story short. My ex and I finally broke up after a month of constant arguing with the main reason of me snooping on her Facebook without her consent for 2 mins according to the history. The reason I felt like snooping through her messages was because she was constantly talking to another guy I had never met before, and also never allowing me to go with her when they hungout. We constantly had problems before with other guys (2 other guys she went to movies with and another she stayed pretty late at a guys house doing HW) but I felt the worst about this other guy. She always reassured me he was a friend but seeing them in pictures on his facebook made me cross the line. So I ended up going on her facebook and lying about doing it, then getting caught. She later tells me on a scale from 1 to 10 (10 being the worst) that it was an 11. Is she overacting or what I did was fucked up to the point of breaking up permanently? Please give me your advice! We dated for nearly 3 months.
<bot>: How bad was it that I snooped on my ex's Facebook messages for 2 mins without her consent? Am I a horrible person for breaching her privacy?