<human>: Can you give me a shortened version of the text?

My Girlfriend [21] lied to me [23] about a party she was going to. She told me I couldn't come because it was a girls night out and they were just going to have margaritas and do girly things at a friend's house. I just found out that this wasn't actually the case and it was just a normal college party. I have no problem with her going to parties and getting drunk around other guys but I am hurt and confused why she lied to me. Is this a good reason to be angry or should I just let it go?
<bot>: Girlfriend lied to me about a "girls night out." actually went to a normal party. should I be mad?