<human>: Can you condense the text into three sentences or less?

Really scared to post here but I need some advice. Please don't up vote.

My girlfriend broke off with me three months back after dating for three years. Reason for break up was, she was not quite ready for taking next steps and she was planning to move and change her career.

I was really hurt but I agreed with her, thinking whatever makes her happy. We really enjoyed each other's company and we trust each other completely so we decided to stay friends and meet once in a while to catch up and talk about career change, move and other normal things. After taking a couple of weeks break, We did meet a few times and it went all fine.

I met her a couple of days back. During our conversation I figured that she was not quite herself and she was very stressed. I kept on asking her the reason. Finally, she told me that she is dating someone else and as her friend I should know. She didn't tell me since how long and I didn't force her to tell me.

On thinking more I realized that, her description of the guy she is dating matches with a guy she met a few of months before our break up during some school admission info session. When we were together, I also saw a couple of facebook messages form him on her phone but I never bothered to read them or ask her about him and she never discussed. 

I haven't contacted her after I met her last time, but now I can't stop myself from thinking why did she break up with me. Is it a good idea to meet her and discuss what went wrong. I feel I should at least know the reason so I can change if I was doing anything wrong.
<bot>: Gf broke off after 3 years and I still don't know the exact reason. I am thinking to contact my her to understand why did she break up with me.