<human>: We are both 23.  Basically, she was on a cruise for a week and we were not able to talk.  She got back and told me a guy kissed her on the lips while they were in the hot tub.  (she was in the hot tub with other girls and a few other guys and they were all hammered).  She had already told some of the girls that she had a boyfriend and she is unsure if the guy knew.  Anyway, she got up and left as soon as she was kissed.  

Some of the girls yelled at her for not yelling at him for it.  Anyway, I reacted that she did nothing wrong.  She expected me to be pissed off or something because she didn't throw a fit or stand up for herself more.

Relationship length is 6 months

So my questions are:

(1) should I be more angry?  

(2) Is the fact that she didn't throw a fit something I should be concerned with in the future if a similar incident arises when a guy hits on her and I am not around?

Could you distill the essence of the text into 1-3 sentences?
<bot>: Gf was kissed while on a cruise by another guy.  She just left when he kissed her.  I am not angry at her for it but have the 2 questions above that I would like advice on.