If a loved one was "...not a friend, not an enemy, and so...", said Vladimir Vysotsky, so it's not friendship it was at all. Often people confuse the sincere attitude of a person toward them, and hypocrisy. In understanding any friend is someone who will always help and will always help in a difficult situation, so much betrayal changes the attitude to life.
Understand that no one is exempt! Will always be people who want to be friends only due to certain benefits, and not just. Especially in our age of rapidly growing businesses and new technologies. In the era of computer and social networking in General is difficult to maintain normal human relations, to say nothing of a full-fledged friendship.
Decide for yourself whether the traitor be forgiven. Everyone makes mistakes, but many repent. To forgive and to understand your friend the same thing. Of course, if we are not talking about something global and incredibly serious. The misconduct can be justified and forget. It is impossible to follow the first impulse - to understand the situation more thoroughly. It may be that part of the blame belongs to both parties. But to forgive does not mean forget. The adage "Trust but verify", can be very useful approach to the relationship between the friends after the betrayal.
It is a mistake to think that loved ones must choose between loyalty and betrayal, so never put them in such conditions. No one is obliged to sacrifice their lives, their interests in favor of someone. In psychology for a long time, there is a Golden rule of friendship: a friend will never put another person into the rigid framework of choice.
The betrayal of close friends - a test of strength and tolerance. The only way a person becomes stronger, because life experience, albeit negative, in order to avoid mistakes.