When a person is seen weeping, we usually interpret that the person is very sad. This usually elicits empathy from an empathetic person. Some people are hyper-saddened by misfortunes of friends, family and even people they have no connection with. Such people become frustrated by their own inability to lessen the problems of others. They over-empathize and want too much to fix the sad person’s problems. They then cry a lot in over-empathizing.
When other people cry they are not sad at all. These other people cry when they are angry or inconvenienced. They feel self-pity. For example, such a person, seeing an ill family member who is in need of support and comfort, may cry copious tears. But, when he is questioned closely you will find he is angry and jealous that his ill relative is getting all the attention and he is getting less attention than usual. Thus, this person cries for himself out of anger, rage and jealousy. Same emotion, crying, but vastly different reasons why.