Definition: Given a real-life anecdote of a complex ethical situation, generate a suitable title that describes the main event/root cause of the situation. Imagine that the given text is a social media post, and you have to write the title of the post, so the users can decide to read the main text or not.
Input: AITA for checking my gf's phone after she started to behave odd?
We already broke up now. We we're in a vacation two weeks ago. We were in long distance relationship in recent three years and were together for more than 5 years. We we're meeting after 5 months and we had planned 2 weeks long vacation in a new country.

From the very first day she started acting weird. She said that the relationship might be over after the vacation. We we're having some miscommunication so I said yes, we can take a break and revisit later. 

So, during the vacation, she was spending more time with her phone. No physical intimacy or anything. I was really frustrated and I was trying to make things better. She said that she was not feeling right to be in relationship or something. And she said that there was no particular reason for leaving me.

In the second last day, I went through her phone. I found out that she was cheating on me for more than 2 months. She even had a another vacation planned with that guy.

Things ended right there. I was shocked and sad. I still have not recovered. 

Now, she has been describing me as a "creep" to our mutual friends for going through her phone. I don't want to respond to that but it makes me wonder what would have happened if if I never knew. 

Do you think I was an asshole for going through her phone? I would feel like shit I had found nothing but my  suspicion came out to be true. 

Thanks for reading!

checking my gf's (now ex) phone after I suspected something odd and found she was cheating on me