Man, you're bigger than her. That is the typical response from your average person. You overcame that! Good for you.

As far as WANTING to have done it, consider this: What are the possible reactions she could have had? She either is not going to care, or she is going to care that you cheated.

If she didn't care, you wasted your time and you had sex with a stranger for no good reason with regards to her.

If she DID care, she would either be angry about it and dislike you more, she would feel crushed, or she may not feel anything.

If she disliked you for it, she will be heated about the whole situation. The dislike will continue on her part. She will tell all her friends how much of a jerk you are because you cheated on her to get back at her. This will hurt your cause, as it will bring you further humiliation. First off, it will implicitly tell everyone that she cheated first, of which you dont care to remind people. Second off, the appearance that she can control you will bring more humiliation to you, as it will make you look impulsive and shallow, especially as it sounds through narrative form. Tell yourself the story without detail and tell me if it does not make you sound this way. In short, she has little reason to brag about cheating on you. Don't give her one!

If she was crushed by you cheating on her, she is probably a sensibly emotional woman, which a breakup on her account would already devistate. If you cheated on her, you have just become the source of her tears. If you leave it alone, as you have, SHE is the source of her tears because SHE cheated. Leave the blame on her.

If she doesn't feel anything, she will either feel something someday, or she won't. If she doesn't, that is some serious coldness, my friend. The kind that would make you thankful she gave you an excuse to break up with her, PERIOD.

If someday she does feel regret, your cheating would have diluted the feeling. Right now, you are completely innocent. You treated her nicely by the standards of this day and age. There is a great proverb that says, "If your enemy is hungry, feed him; if he is thirsty, give him something to drink. In doing this, you will heap burning coals on his head." If she is ashamed someday, that day is when the lumps in her hair will spontaneously combust. She will be in great anguish. So be kind to her, or at least ignore her. Set those lumps in place, Leader.

Quick recap:

Unaffected by you cheating makes it pointless.

Anger from you cheating will immortalize the story of her cheating, making it unfavorable.

Pain caused by you cheating will shift the blame on you and will dilute any present or future guilt.

Remorselessness makes it imperative that you run away from her as quickly as possible, nevermind cheating or not.

If you ask me, I think you did the right thing morally AND strategically.

 No two wrongs dont make a right

 So what 2 wrongs make a right?? What goes around always comes back around. Remember that!

 I know it must feel terrible to you right now. You didn't deserve to be treated that way.

You have shown tremendous integrity in the relationship and as a human being. You can be proud of that. It was right that you held to your principles, and she doesn't sound like someone who can appreciate them.

Don't look back, Leader. Live up to your name. Living your life in a principled way means you won't have to ever tell anyone what a great person you are--they will see it in the way you have lived your life, and you will know it, also.

Congratulations on moving forward, and so sorry for your hurt. There are many ethical people in this world, and you have all my best wishes to find the one that can appreciate and will adore what you're about.

 I know its frustrated when you find your girlfriend have cheated you, but its no point for you to cheat on her as a revenge, its not love! Forget about her, I am sure you will find a nice girl who deserves your love.

 Nope --you were the decent one that remained faithful. You should move on and find someone else, someone that will appreciate a man that loyal in his relationships. Don't let this one person ruin your sense of morals or ethics -- you can do better and be respected and appreciated with another woman.

 Why would you want to stand to her level Immature/be the better person in the long run fate will have its reward

 Two wrongs don't make it right. Cut your ties with her and be done. Find a better woman since what you had was not a woman at all. Good luck and better luck next time.

 If you loved her too much(your not cheating first shows that), then you would have felt bad too AFTER CHEATING FIRST. So don't regret for not cheating. You can pat on your back for your honesty.

 Don't thing you should have cheated. Think about how you felt when she cheated. Would you like to make someone else feel like that?
(btw i have never been cheated on but I'm just guessing it's not a nice thing to happen)

 Whats done is done. Don't second guess yourself besides now who is the cheating (expletive) and now who is the innocent nice guy getting the new chick.....hahah good luck bro.

 It won't solve anything. When you fight fire with fire, it just causes more fire!

 Two wrongs don't make a right.

 What's the difference between you 2.

 Why risk your own moral standards and reputation, because someone else did?

 Two wrongs dont ever make anything right--besides now you can walk away knowing that you are better person.

 Not cheating was the right thing to do, you have a better rep. If you keep a clean slate.

 NO i don't think you had cheated because she has already cheated you had just taken a decision which is good one.

 You did the right thing

 No, you should not have. Two wrongs don't make a right.

 Cheating is not acceptable in any circumstance, it would make you just as bad as her have more respect for other people and most importantly more respect for your self

 NO, cheating is never a good thing for anyone.

 She cheated you, forgive him.. It's not your mistake, its in her

 It's like tit for tat.To Forgive is equal to godliness.

 How would you cheating back on her change any thing . Then you would both in the wrong and two wrongs don't make a right

 Two wrongs never make a right, never do it.

 Cheating - what a wicked web we weave when we conspire to deceive! Once you cheat, your integrity is gone, your moral foundation is uprooted, and your anger for her promiscuous actions is negated. Stay strong and be the bigger person - always. Don't let her take away your self dignity by stooping to her level. It only hurts you in the end. I know. I've been there and I don't ever want a return visit!

 Wow. Ever heard "Two wrongs don't make a right"? Well, they're right. If you cheated on her because she cheated on you ; you both look like cheaters & players. Can that do any good for your next relationship? No! Who wants to go out with someone who has a reputation like that?

 How were you to know? You would have had to live with the guilt that may have been worse. I hope you can find some relief in knowing you did the right thing.

 No, you were wronged. You may feel like you've should've cheated. Now you think of all the signs that were in your face and you dismissed them. It seems you put your heart on the line and got caught in the crossfire. If you would've have cheated you would be no better than she. You must know that she will never be truly happy until she comes to terms with what happen between you two. Normally, people who cheat are always looking for something that they never find or passed by, their to busy cheating. When you see her, whenever, if ever, you can look her in the eye without any shame, guilt, or anger because deep down you both know she was wrong. Then you can throw back up in her face. Maybe you should forgive her, Maybe you should take her back. HELL NO, but if you do reconcile and even get back together, you have the advantage if you use it. You'll have to get thick skin, and a tough heart. Because you will play her ass like a PS3. Then you leave her. That might be too vicious, but it is an option.

 Cheating is not a good thing shes just damaged goods you will find someone true and the last thing you want is to think they are going to cheat and mess it up. Stay true

 Whoa.... You want to sink down to her level...That's just whacked up thinking.

That would demean yourself even worse. You would be remember as the unfaithful unmoral one. Do you really want that.

Be the better person

 No, you shouldn't. Your gf cheated on u, it made u feel angry and hurt. But there's no use you should have cheated on her first. Will u feel happy if you really hurt her? Now, It's better for u to let her go, and There's no Humiliation in your relationship, since you broke up, just move on and live your new life, let her go and try to live better than her. You'll find a better girl than your ex soon.

 Two wrong do not make it right. You broke up with her, now it's over, move on with your life. What's in the past, leave there and
start with a new girlfriend.

 Heed the old adage"two wrongs do not make a right"