Tell him. Or do exactly what the person above said. See his reaction. If he gets mad or breaks you down you will be able to know how selfish he is! Cheating is cheating but if he cheats then he acts like nothing happens and doesn't show remorse then he has probably done this many times. You need to stand up for yourself. Trust me there will be someone who values you. You are strong and you said you are attractive so you will find someone else! The fact that he got cheated on should not be sympathized. He knows the feeling, the hurt, the humilation and yet he did it on someone he "loves." No, that is a pathetic excuse. If you decide to to stay with him be prepared for a long recovery because you will not forget this incident tomorrow. He has to be an open book with you and he has to make it up to you in every way possible. Lastly, if he uses you as the excuse why he cheated then your husband is a boy and should be left again....

You cant just let it go. And he will do it again. 

Your husband has dishonored himself. He can never regain what he threw away. You will not be satisfied with him ever again. Your love for him has been dealt a mortal blow. It will slowly die and turn into contempt. As far as you are concerned, be honest, do not keep secrets from him as he has kept them from you. Tell him you saw him. Ask him how many and for how long. Make him tell you everything. It will help burn the love for him right out of you. Contact and attorney and get a divorce. Move on with your life, chose better next time. 

Sex is sex. I am a husband too and i cheated my wife.  I can't resist. But is just sex. I love my wife, i support her in everything. But i love sex. I love the adrenaline, the discovery of another person. I have an advice for you: Don't let this pass. Confront your husband. Don't keep this suffering for yourself. Let your husband suffer too. Let him know that you are suffering for this. But keep this in mind: Even cheating, maybe your husband still loves you. Maybe he stills feels atractted for you. Maybe. I don't know him, so obviously i can't speak for him. I speak for me and i am a cheater too. I love my wife, i admire her, i feel atracted to her. The common sense says that when we loves someone, we only feels atracted to that person. Bullshit! We are animals! We fuck! And we are individuals. Maybe some people are natural faithfull, others, natural cheaters. Sometimes i wish that my wife have sex with another person, to experiment and discover the pleasures of sex. Because i love her. And I know that she loves me.  I'm not affraid to let her be with someone else for fun. I even propose that for her, but she is a conservative (i don't know if this is the right word, english is not my native language) She doesn't accepted. But i can't. I need to live. I need to fuck other people. So i try to make this in the more discreet way possible, to not hurt her. But don't suppress your feelings. Decide if you can live with a cheating husband. Ask him why he's cheating on you. Ask him if he loves you. Ask yourself if you really wants the divorce. Your are attractive, you will find someone else. But, how do you will know that this someone else will be more faithfull than your husband? People lie. All the time. And the most important advice: Forget about crap advices on the web. Your life is yours. You decide what to do. Be brave.

"To the Male Cheater" You sir are an ass hole and I hope your wife divorces you! Cheaters do not admire their wives. You take advantage of your wife. You are scum. My husband cheated 3 weeks before our third child was born.  It's easy to say you love someone, much harder to show it! 

To the OP: Confront your husband! Ask him what he was doing when you went out. Give him a chance to come clean. This will eat away at you if you don't and you deserve answers. I am still with my husband. He cheated 3 months ago. Staying is the hardest thing I have ever done. I have not forgiven him but we are working toward reconciliation. His affair was a one night stand and he didn't use protection. I can't tell you if your husband loves you because I don't even know if I believe my husband loves me. The only thing I can say, is to talk to him, question him, and keep communicating. Do not keep your pain hidden, let him see the damage he has caused. You deserve better! 

You don't have kids of your own, confront him and leave now.  Actually, leave him first, then let him know why you did.  Do you have friends or family to stay with until you can get back on your feet? Find your support, stay strong, DON'T, DON'T, let his words and his lies make you waver. Most people who cheat are excellent liars, they are pros at manipulating people - don't let him do this to you.  If you take him back, you will regret it, because it will only happen again.

Cut and paste and read this article, I agree with every point in it: http://www.huffingtonpost.com/2013/08/11/cheating-spouse_n_3721907.html

Let me say this again - IF YOU TAKE HIM BACK, YOU WILL REGRET IT LATER.  Couples who continue to stay together after one has cheated and have a better stronger relationship ARE VERY RARE.  What usually happens is that the one who was cheated on will ALWAYS have that doubt in their mind, cannot fully trust, and will never get over the hurt and betrayal.  Don't be this person.  YOU DESERVE BETTER.