You need to reevaluate some things then , I think . Her wanting to go out and party shouldn ' t make you feel bad , not one bit ! You should be happy that she ' s making friends . You should be happy that she ' s socializing . You should be happy that she ' s developing into her own person . What do you think she should be doing ? Waiting for your texts and calls at home , instead of having a life outside of you ? You sound really controlling . I know you ' re saying that she can do what she wants with who she wants , but she ' s not going to feel like you mean it If you ' re perpetually guilt tripping her for it , feeling hurt at the idea that she ' s having fun without you . This is directed that you don ' t like that she went to a party . If she ' s always been truthful why are you casting so much doubt on her in a situation as sensitive and hurtful as this one ? Empathize with her instead of criticizing her . Realize she immediately came to you with the truth , as soon as she found out about it and had the appropriate means to communicate the situation with you . Be thankful she didn ' t try and hide this . Think bigger picture . The real betrayal is your girlfriend trusting the people around her and being severely let down . Be angry on her behalf instead , of at her .