When you have been cheated on, the first thing you have to do is decide if the relationship is worth saving. Both of you must really want to work at gaining trust and healing from the pain and disappointment of the betrayal that goes along with the infidelity.
Communication is needed to understand what caused the infidelity in the first place. This is crucial in hopes of preventing it from happening again. Couples counseling could help with an unbiased third-party. He has to earn your trust again. Trust is very hard to gain, once it has been lost.
Don’t obsess over information about the other woman. It was your man who betrayed your trust, the other woman doesn’t have any loyalty to you. You need to know if it was a one-time affair or a lengthy affair. A slip up is easier to forgive. If it was with an ex, that could mean there are still underlying feelings between them. That would pose a problem in trying to salvage the relationship. If he has cheated on you before or he has a pattern of cheating in all of his past relationships, he most likely will cheat on you again.
Separation is often necessary to let him know the severity of what he has done, and to let him feel what it would be like without you and to make sure he takes the consequences you give him, of a repeat occurrence seriously. You may also need the time apart to allow yourself to heal from the hurt. He must show remorse for what he has done and ask for forgiveness. Let him know how much he has hurt you. Ask him how he would feel if you were the one who had cheated on him. Sleeping with someone outside your relationship to get even doesn’t work. It may make you feel better, but only temporarily. Two wrongs, don’t make a right. You shouldn’t sleep together until you have forgiven him and are trying to put the relationship back together, or until you feel you can trust him again.
If you decide to stay together, you MUST forgive him, although you will never forget. You will have to let it go and move on to repairing the damage he has caused. You can’t keep bringing it up and badgering him. You must tell him the consequences of this happening again. You should be prepared to stand by the consequences you give him should he be unfaithful again, otherwise he will see your threats as nothing more than talk, without any action to back it up.
After you have tried your best to forgive him, if you are still unable to get past the betrayal of the affair, the relationship is over. Some women can’t allow themselves to trust a cheater again. A relationship without trust isn’t a relationship at all. It will only cause constant accusations and suspicion on your part. You owe it to yourself to be happy. In this case, it would be best for you to let go and move on.