I was asked by a friend this question the other day and I gave no exact reply because she's too emotional disclosing her situation and we just have limited time, so I just stayed listening. Anyways, let the experts give the advise and I extracted hereunder from Dr. Phil's website, http://www.drphil.com/articles/article/16
Were you cheated on?
•It is absolutely vital for you to move forward with life and love. Being willing to trust again is key. Take things one step at a time.
•Don't try to make sense out of nonsense. Rationalizing your cheating spouse's behavior or sympathizing with him/her is pointless. It is never OK to go outside of your relationship to solve problems within a relationship. It's not your fault.
•Time heals nothing. It is what you do with the time that matters.
•Remember that it is better to be healthy alone than sick with someone else.
•If your partner wants back in, he/she will have to earn his/her way back into the relationship. Renegotiate the relationship in a way that works for both of you.
•There comes a point in time where you may have to draw a line and say, "That's it, I'm done. I'm not mad at you. I withdraw my feelings, I withdraw my emotions. You just go do whatever you're going to do because I'm not going to live like this anymore." Don't stay together for the children. Remember, kids would rather be from a broken home than live in one. They're much better off with one well-adjusted, happy, thriving parent, than they are with two who are cheating, lying, fighting, and living with stress and pressure.
•If there was a child born of the infidelity, understand that your spouse will forever have a relationship with that child's other parent. You have to make the decision about whether you can resolve to be part of that or not.