There's one thing here that's clear to me whether you choose to accept it or not: you already don't trust her. The fact that you're snooping through her text messages is clear and convincing evidence of that. If she's already broken that trust after only a year in the relationship, she'll most likely do it again. I'd also caution you that you'll find it nearly impossible to truly trust her again. The thought of her cheating will always be in the back of your mind and you'll never be able to get over it.
It's time to move on. No one is worth the value you're giving her. If she really was "the one" she wouldn't cheat on you.
Also, that thing about respecting the guy that took back his cheating wife. That's something that only sounds good when it happens to someone else. As others have pointed out, if you do this, she'll lose respect for you and then the relationship will REALLY be over.
I'd also caution you that, now that she knows you know, one of two things will happen. Either she'll wait for you to take action, allowing you to confront her and maintain your dignity or she'll gather herself together and dump you when she's gathered the strength. Now that she's aware you know, the clock is ticking. Every second you remain silent loses you more and more respect in her eyes.
BTW, when it comes to these things, it NEVER works out the way you plan.
