What should I do?

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If you both want to save the marriage, your wife needs to admit to the affair and end it as of this moment. She needs to have no contact with the man she was having the affair with, even if this means quitting a job.
She needs to explain why she had the affair--what were the issues she had in your marriage that made her decide to be with someone else? She should also agree to marital counseling with you, or at the least some counseling with a priest or a pastor.
If she has no interest in giving up the affair or going to counseling, there isn't a lot you can do to save the marriage.
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its almost impossible to please anybody now days and cheaters can go long periods straight but will cheat again .. send her packin and get a hiv test unless your into self punishment then give her another chance
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First thing you need to do is recognize that there are serious problems in the marriage, and that your "wife" is not the honest, caring, considerate person that she claimed to be. Second thing you must do is immediately talk to a lawyer and find out what your options are, as they vary by state. Third thing you do is objectively evaluate your situation. Are there kids involved ? If you have no kids, then divorce her immediately. Remember women & men are different. Men cheat because of the physical. Women cheat because of the emotional attachment, thus when a woman cheats it is almost always over. If you elect to stay in the marriage it is CRITICAL that you evaluate your financial contributions from this point forward. If you are the primary financial provider, you must, you absolutely must protect your financial interests by declaring a legal separation. Being separated doesn't necessarily mean you are getting a divorce, but what it does mean is that you will not be liable for future financial obligations.Set up separate bank accounts, and make sure she is contributing financially to the household. Have an attorney draw up a QRDO, and immediately divide the 401k. Essentially treat the marriage as a financial partnership, because essentially this is the only way you can possibly save yourself. Next both of you go to counseling and see what happends. Lastly if you even remotely suspect her of continuing the affair, spy on her. Load software on the computer to get her keystrokes. Check the cell phone usage. Chances are if you think she is cheating, then she probably is. Good luck. Keep the faith.
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First, catch the wife in the act, that way, she doesnt get half of the marital assets nor custody of the kids.
Here no matter the reason you go to court for divorce it's a no fault. Though in this state it's on the record that a woman actually served jail time for having sex with another man. Go figure. Unless the couple has a agreement before hand, everything gets split. 50 50. Sorry buddy she gets the billard table you get the shafts I mean sticks.
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Once a cheater, always a cheater. My Mormon wife cheated on me twice! And she did the same thing to her ex-hubby.
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If you suspect your wife/spouse/partner/lover is cheating on you, even if it is the most difficult thing for you to do, give her the benefit of the doubt. It's not always right or correct, even as being our first instinct, to point a finger and accuse a woman of cheating. Everyone knows that it is scientifically proven that men are 13x more likely to cheat than women, however, there are the few and far-between women that actually DO cheat. Think of it on a positive note, though: if she cheated on you, it wasn't meant to be, and you can go on with your life after a time of which you feel comfortable, and move on to bigger and much better things in your life.
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Understand that you now have the answer to whether you wife is the cheating type. Two options:
1) Stay with her; which is showing her that there is no penalty for doing it. Then wait for the next time, which will certainly be in your future.
2) Be hurt,betrayed,and sad that she ruined the relationship built on trust. Talk out you feelings with her to get things out for both of you. Then tell her you understand her explanation, you still care about her, and accept what she did. Then tell her you hope she understands now, just like she said she did when you got married, that you can not be with someone that you cannot trust. If she "learned her lesson" or "mistake", remind her that now she knows the consequences, when she finds someone else. Then offer to help her pack.
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As a Muslim, this is punishable by death! You see people, God gave us the Ten Commandments so we can live righteoulsy. If we all abide by these, there's no need for counseling, no expensive lawyers to pay, and above all no plague on this world. But man wants to create his own set of rules in life. Not a good idea..because no one can ever beat the Laws of God. It is perfect in every sense. If a wife cheats, she'll burn in hell for all eternity. This is a fact and you must always remember this. How could you enter Paradise if you had cheated on your husband!!! This is insane! Shame on those cheating wives. You had made a lifetime commitment to your husband, and you should never cheat on him.
If ever this happens to you, may God forbid... tell her this straight into her eyes; " May God have mercy on you on the Day of Judgement".
All shall feel the wrath that awaits those who cheat! May God the Almighty have mercy on your souls.
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Sins of the flesh. The flesh is weak. SEX is a basic instict in all. Though I personally beleave in a couple mantaining the basics of a relationship won't be shocked when a affair is discussed first. "open" relationships or swingers fear no pain from having sex with others. Watching is fun & builds a closness like nothing else can.
In PA. adultery is punishable up to 3 years in prison if proven in court (1997 women servered time-3 months). Death now hmmmm. I am thinking to myself that her life is less than my own. A woman is to be treasured...shared if need be. Depends on the person/people. If you allow yourself such rage & selfishness to want death because your ego your frail feelings are hurt than you can have that 'god'. My GOD forgives & allows mistakes or growth. But in the end if you can't talk to your mate about fantasy or outside relationship sex as a release.. I.E. Roll play her another woman as she's blindfolded. Call her the name aloud. If you can't be honest & state needs... I need to explore sexual more with you. He should help....not push her away. Anyway I see it like this: 56% of American are divorced. Over 70% cheat on their spouse. LIEING about it the entire time. Caught on video & still deny it too. This country will never grow as a strong nation if the families aren't able to stregthen the next generation by using example as a teaching tool. Watch parents rationly solve issues like infidelity or even minor ones like compromising on financial investing. One year use her plan. Next use his. See which is working for the growth of/to wealth. I would not hide the hurt & distane from partner but I wouldn't allow it to KILL a part of myself. Couples that marry are YOKED!
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You need to talk to her about it. Tell her it has to stop and then suggest going through counseling, together and separate. If she doesn't want to end the affair, you will probably have to leave her, or just deal with the affair. It will be healthier for everyone if you and she separate if she isn't willing to stop though. This is a very tough situation and you need to do what you think is best for you.
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Tell her you know, and tell him you know, make sure he understands you wont put up with it.
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Give her an ultimatum: Either immediately fire her secretary, end the affair, and go to marriage conseling with you, or you'll take the kids and leave. If she refuses to stop, pack up and leave. Tell her you won't come back until she stops and agrees to go to couseling. You don't deserve to have to put up with that sort of thing.

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