If it is well behind her and she is committed to moving forward you need to trust her. She has broken your trust, and it is hard to truly move on from that. It is her job to reestablish your trust, and it is your job to try to be positive and to let her do what is necessary to show you that she is committed to your marriage.
What things allowed her the opportunity to cheat before? Is she avoiding those opportunities? Is she keeping the other person out of her life? If she keeps that other individual in her life, and if she keeps doing things that leave her vulnerable to a relapse then she is clearly not committed to the straight and narrow. I'm not saying that to be mean, I'm saying that honestly, steps need to be taken to avoid these things! No one is perfect, NO ONE can avoid the temptations they put in front of themselves, I don't care WHO they are! If you freaking love lattes and you purposely drive a route nearby your favorite coffee shop, chances are you will go buy a freaking latte!
Also, it is important to confront the issue at hand - what made her stray? That is not to say you should blame yourself - you are who you are, she is who she is, but after eleven years of faithfulness what caused the break? What does she need to feel strong in your guys's relationship? What do you need to feel strong in your relationship?
It is not constructive to bring up her cheating, no matter how much you want to, no matter how related to an argument or issue you think it is. I know that that is what's on your mind, trust me, it's on her mind, too. And she is dreading the thought that it's on your mind, and she is wishing she could go back in time to change what happened. But she can't. Neither of you can. You can only stay the course, and try to move forward.
Keep the line of communication open - you both need to check up on each other's happiness and security. It is important that, when these issues are brought up, to not take comments personally if they are spoken in a sensitive way. This is a huge problem when dealing with these issues - trying to communicate feelings while each person is taking everything personally as an attack! It's not. It's just an effort to share so you both can improve and move forward.
Time does not heal all wounds, but time does help us learn how to cope and how to move on even if everything is different. If you are both committed to each other, to your marriage, and to love, you will find a way.
