HIV and AIDS is a weird disease. On the one hand you hear that you have a terminal disease but, due to the long disease progression you might only become ill and die some years in the future.
We do not always understand what emotional impact HIV has on an individual's life. There are four potential phases a person might experience from diagnosis to a phase of acceptance and rebuilding. The phases we will cover will refer to the HIV infected person who is still healthy like me.
The first phase is the shock phase. When a person hears that he is HIV positive, there is normally some kind of shock reaction. This reaction differs from person to person. Mostly the first shock reaction includes some kind of emotional reaction. This could include anger, crying or a feeling of total numbness.
In this initial shock phase people might be so shocked that they say or do things they would not normally say or do; things they would later regret and this is called irrational behavior. For instance, a person might walk out of the doctor's office and start to spend money - buy everything he always wanted. Other people might say to themselves or to others: "I'm not going to die alone - why must I be infected - I am going to take some others with me."
Fortunately the initial shock phase does not last long, usually a few hours to two days.
The most important thing to remember if you should ever have to tell a person that he is HIV positive is to realize that this person is very often shocked upon hearing the news that anything said after hearing this tends to fade from their memories. Counselors or doctors sometimes forget this and would then try to provide all the possible information and prevention messages - but at that stage the person is not absorbing anything. Proper post-test counseling however is very important. It will help the person to think about the consequences of the news, how they will cope up in the next few hours, whom they will tell - if they want to tell, etc.
Source: Channels of Hope workshop manual.