Cheating and second chances

Me and my bf have been together for 6 years , I NEVER went thru his phone until one day I got a gut feeling and I came across some messages between him and another female. I approached him about it, I never mentioned how I came across the messages but I let him know I saw them and that I wouldn't stand for the BS. Of course I was HURT! It took some time but we seem to be on good terms there are some times where I think back on how hurt I felt at the time but I tell myself we agreed to leave that in the past and move on with positive changes in our relationship .... Do you all believe in second chances when it comes to cheating?  And how do you move on?