People that lack empathy are regular, every day people. The issue is that most people equate sympathy with empathy, but they are very different things. Sympathy is understanding how you would feel in a situation you observe. You feel for the person, understanding the pain and hurt you would be going through if it happened to you. Everyone has a different capacity for processing this and not everyone expresses this understanding equally. So usually someone said to be lacking empathy is someone who lacks the experience of the situation to understand the pains or joy another is experiencing. They may seem confused or unconcerned. It doesn’t make them bad, per se, just poorly informed.
Empathy, on the other hand, is different. There are similarities, but they are not the same. Empathy ignores the surface situation. Someone with empathy will experience the emotions of others around them even if the surrounding circumstances contradict those feelings. An empath will, ironically, often be accused of lacking empathy because they seem detached from sharing the general consensus of sympathy. They don’t care that their mutual friend’s long term relationship ended, even though within they feel relief, not pain. They aren’t excited for the happy couple getting married, even though the couple are feeling fear and dread, worries for a financial future, feelings of being trapped. People often think of empaths as bipolar or suffering Depression, especially in adolescence when they are bombarded from all sides by conflicting emotions they don’t understand and have no control over.