Infidelity is a very devastating weapon to every marriage. It may obliterate everything you've built up over the years with your partner within a matter of seconds. Everything important in you life seems to be destroyed; leaving feelings of God know what as to How and Why this happened. Having to go through infidelity in your relationship doesn't mean it's the end of everything; there are ways to get over it, recover from it and move on away from it.
We all believe in hope and faith. And where there's a will, there's a way. If the love you thought you shared with your partner is strong, there is a chance you can re-build your relationship, but it won't be easy, once you loose trust in a person, it becomes hard to trust them again.
After going through a very hard time, you and your cheating partner may separate for a while to take time and space to think of what just happened in your relationship. Being human, we all should have the ability to accept, forgive and build a new trust towards each other. Trying to figure out what caused the problem that made infidelity came into your life in the first place is the first step, because nothing is all one person's fault. Look deep into yourself, and then ask yourself what was it in you that made your partner do such a thing?
The same goes to the cheater; he or she needs to realize that it was a stupid thing to do, while realizing what true love really means. The moment you wed and say "I do" it means to live and share your lives through everything, good and bad. Only when you have come to that realization will you begin to realize that your significant other has always been there for you no matter what happens.
When the two of you finally reach a point and are able to sit down and talk about what has happened in your marriage with a clear view of what caused infidelity, you must also decide Is this the same person I want to be married to. Talking about it will clear the air as will talking about each other's flaws.
Approach each other face to face and solve every single issue that broke down your relationship. Don't let your emotion and anger get a hold of you. Be rational, open and firm. With hope, both of you will manage to solve the problem on your own.