Betrayal is probably the most devastating loss a person can experience. To be betrayed, the person must first experience trust in the betrayer. It is fairly impossible for you to be betrayed if you did not trust the individual in the first place. Therefore, the definition of betrayal involves the act of someone violating your trust in them.
For instance, a child is betrayed when he or she is abused by the parents who are supposed to love, support, and protect the child. Betrayal is when someone you trust lies to you, cheats on you, abuses you, or hurts you by putting their own self-interest first.

In our society, we have trouble understanding the concepts of loss and grief. We understand that when someone dies we experience loss and grief, but frequently we don't recognize the other forms of loss that we may experience in life. Loss can be losing a person through death. However, it can also be losing a part of that person such as through illness.
Loss can also involve things that are less tangible such as trust. When an individual is betrayed by someone, they lose trust in that person. In trusting another person, we believe that they won't hurt us; when they do hurt us, we then have the awareness that this other person has the capacity to hurt us. Therefore, we have lost something very important to the relationship.

So, given that betrayal is a loss, it is necessary to understand the process of grief in order to deal with having been betrayed. Most often, when people have been betrayed, they have overwhelming emotions which are so intense that they are unable to make any sense out of them. Therefore, if you have been betrayed, you need to understand what these emotions are and why you are experiencing them before you can really take any action.

A common stage where people become stuck, especially with the issue of betrayal, is in the anger stage. They become so focused on the wrong that was done to them that they never fully experience the other emotions such as the sadness due to the loss of the relationship. Other times, people become stuck in the denial stage by becoming so focused on forgiveness. They are so quick to want to resolve the issue that they deny the full experience of the anger and sadness involved in the loss.

It is particularly painful since it comes from a person whom you trusted. However, it is also true that a person can only betray you if you trust them. Do not blame yourself if such an event happens with you, but definitely learn from the incident.
Moreover, try to take these betrayals as life term experiences that taught you valuable lessons about your priorities in life. So always give a deep thought before taking any decisions and commitments.