<human>: So my current gf and I were dating for 3 weeks before I asked her to be official. She was dating another guy at the time, which she lied about for a while but I am told that this is just the way the game is played. I don't have much experience dating.

The first time I asked her to be my gf, she said no and she said she needed more time to think about things. The next night she spent with that other guy she was dating.

The day after that, I asked her again to be my gf and she said yes, and she never went back to see the other guy. 

My question here is should I be mad at her for anything other than lying to me that she was dating someone else at the same time as me? 

Technically she didn't do anything against the rules as we weren't officially together the night she spent with the other guy.

It kind of hurts my pride however, that she didn't say yes to be my gf the first time and went back to the other guy for one last night before accepting to be my gf the next day.

Am I being immature? Is this just part of the dating game that normal people would come to expect?

Our relationship is more serious now and she has been perfect since we were official so should I just be content with that and move on?

Thank you for your advice, as I said I'm really new to the dating game.

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<bot>: She slept with a guy after I asked her to be my gf and she replying she needed more time to think about it.