<human>: Hey guys, My girlfriend and I were together for 5 years, She decided that she wanted to break up because she was unhappy, Said I was always grumpy and didn't understand her. 

She had been playing online games staying up all night for like a solid month and going on webcam with these guys. Hence my grumpiness... I confronted her once or twice saying that I didn't really feel comfortable with this and asked her if anything was going on? She said no every time we talked. 

Fast forward a month later and she wanted to break up, in addition to me being grumpy she said that the main reason she wanted to break up was to better herself and stop staying up all night and get a job or figure out what she wants to do with her life basically. I could understand this because she really wasn't doing anything and I wasn't able to motivate her to do anything. So she had some opportunities at her mom's house to do something with herself.

So we broke up, and she moved out... I asked her once she had left if she had feelings for those guys online. and she said she doesn't know.. maybe.. and that she was just flirting with them and then it came out that one of the guys was in to her. but she claimed she shot him down or something but then went on to say her going online and talking to these guys was an escape from our horrible relationship basically. She never told me anything was wrong with the relationship or that she was unhappy untill she told me she wanted to break up. Also found out that when she got to her moms she was online and flirting with these guys already, less than 12 hours after she moved out.

I feel really betrayed or pissed off or both and feel lied to... How do i deal with these feelings? I told her how i felt but it didn't really help and she seemed to just want to fight about it.

Can you provide a brief rundown of the text in within 3 sentences?
<bot>: Girlfriend flirting with guys online for last month of relationship, thought something was up but she said No, How do i deal with these feelings?