My wife starred in a porn movie while on holiday

Hi.

My wife that i have been married to for 11 years starred in a porn movie recently.
I don't see a reason for it.
We both work, she has a decent job and a decent wage, own our own home, went to college when she was younger and as far as i am aware never cheated.
We have two children together, but recently i was hit with an absolute bombshell.
Her cousin was getting married and as part of the hen night they went to the algarves for two weeks.
After 10 days i received a message on my phone from her saying "i am really scared, i have done something stupid, we need to speak".
I suspected what it was, but she would not actually tell me on the phone and said it would have to wait until she came home.
However after not agreeing to wait, and after phoning her constantly, i finally received a message saying she had taken part in a porn movie. WOW!
When she came home we had lots of arguments, and i did call her names, and she temporarily left and went in to somekind of shelter for a while, but she came back, sleeping in the spare room for a while.
She did not fully tell me about it, and she did not receive a great deal of money, and she had no clue when this movie was due to come out.
It was actually me that found it, and therefor it was me that told her that it was finally out.
When i sat down and watched it i just could not believe what i was seeing, she had divulged that there was more than one man involved but not how many.
I can also see that this was something not shot over one session, it starts on the beach, and the moon is out yet finishes in an appartment and the sun is out.
She says when she first went to the beach she had previously not agreed to that amount of men. And that the scene in the appartment was not part of the original plan.
She also say's while she was in the shelter she gave a total of 3 men oral.
Why would she do this after so many years respectable? I remember the days she would even tell me that i was the only guy she wanted and even gave me a hard time for watching porn, stating the girls in those movies are all sluts n slags