Of course, betrayal of a person close to you is a serious shock to you. Your relationship has been shaken and you can not trust him, as before, but how to be? To restore everything you need time and his attention.
To understand why there was treason, and make the right decision, bring yourself into peace of mind. Go in for sports, go on a trip, go to work with your head. And only when you can find inner balance you can soberly assess the problem that has arisen before you.
Do not make hasty conclusions in a state of affect. To decide how to do it should be a very long time. In this situation, there are a lot of exits. Do not rush to break off the relationship sooner, it's not the only way out of the difficult problem.
If you love your man, then act. Direct your efforts to personal pleasure. Change your image, your actions. Try to save your pair. Become independent, thereby you can attract your wrong man. And your relationship will break out again and become stronger.
Become a mystery to him. Be confident in yourself and in what you do. Meet, as rarely as possible, and after a sudden appear and make love. For him it will be an emotional splash, after which he will feel guilty and will begin to regret that he has changed you. He will often think about you, will dream of meeting and that you will forgive him. And at that moment he will understand that the woman he was looking for so long turns out to be always near him.
Of course treason is a great loss of trust, loss of love, loyalty. If your relationship is strong, then in time you will reconcile. If the feelings are not strong, do not grab for them, like a drowning straw.
Treason can be both the end of your relationship, and the beginning. The choice is yours.