You need to talk to her and listen

Sounds life she was hanging out with her old friends. You sound incredibly jealous. I mean she tried talking to you about it while she was drunk and you freaked on her. You then doubled down again the next day.

Again you snooped through her phone instead of talking to her about it days later. What if you hadn't found anything?? And was it the first time you've snooped through her stuff because you felt suspicious?

You keep reacting irrationally. She has reason to be defensive and withhold telling you stuff if you're going to be volatile about it. And I doubt it's the first time you've been like this.

You need to communicate with her. And yeah she's going to be upset you went through her phone so please don't use it as excuse to make it okay because you think you found something. Trust runs both ways and there are issues on both sides.