There is a difference between forgiving and forgetting.
The fact that you did not file for divorce or walk out on her proves you have forgiven her on some level.
However you no longer "trust her". There are 6 traits found in every happy relationship and trust is one of those.
It takes a long time to build up trust again after there has been a betrayal. In all honesty it is the person who committed the betrayal that should be doing all they can to reassure the person they've hurt that it will never happen again.
In other words you should be seeing efforts on her part to bend over backdwards to EARN back Your Trust.
Instead you state you "caught her again".
Is she sorry she hurt you? or Is she sorry she got caught?
Are you trying to forgive someone who is not seeking forgiveness? You mention you have "average looks" as though that may have contributed to your wife cheating on you. If looks were that important to her she never would have married you!
I suspect the two of you have not come clean about what took place and (why it happened). You may want to try couples therapy to get to the bottom of it. One thing is for sure you can't spend the rest of your life tracking her, reviewing cell phone records, quizing her on her whereabouts, or making her prove she has nothing to hide. Eventually she'll walk away from that type of police state existance.
As I said earlier it's up to the person who betrayed you to "volunteer" to do whatever it takes to "Earn Your Trust".
If you are the one making demands that she does it, in my opinion that's an indication she isn't being "proactive" about wanting to heal the relationship. To forgive someone without honest contrition on their part is setting yourself up for future heartaches down the road.