I also had a somewhat similar experience a few years back. I was in Iraq and my wife at the time was increasingly distant and just all around different towards me. I tried talking to her about it several times but I never really got anywhere so one day I resigned myself to dirty deed of checking her email. I knew her password as she did mine, we were married after all but I had never checked her email before and to this day I still feel guilty about it. When I found out she was cheating I confronted her about it and even though I felt justified that I was right in my assumptions and I'm glad that I found out sooner rather than later, I'm not proud of what I did.