Found txts on husbands phone...

Stephanie • Southern roots. Jersey attitude.
Hey all. Serious topic. I've had this gut feeling the last couple weeks about my hub being sketchy. Haven't said much other than generally beating around the bush to try and see if he would mention anything. Just checked his phone and our phone bill. He has texts from his "best friend" badmouthing me up and down, with no defense on my behalf from him. And another convo from a girl that I noticed he has been deleting but part of the most recent goes as follows:
Her: do you have Instagram?
Him: no I don't sorry
Her: well you should get it because I don't think we are friends on Facebook because I didn't want to see wedding pics
Him: sorry.. yeah
I'm so upset that he is taking rude talk about me from his friend and also texting this girl (I also saw a 22-min call TO her this past week on our bill).
The dilemma: do I confront him about it and admit to snooping?
Or is there another way to "catch him" so he sees me do it?