People have affairs for many different reasons. Generally first off, people have affairs when they have a mental disorder. The disorder makes them feel excited and thrilled about the fact of being able to have this secret, hiding it away from their significant other and family. The thought of getting caught at any time secretly thrills them and drives them on. The other reason is for companionship and the need for human intimacy. Some people simply do not get the intimacy and love out of the relationship they currently have. Their spouse may be sick, or have a problem, or be abusive or unable to fulfill some need that they have. The final reason people have affairs, is because they just fell out of love with their significant other. But out of respect for them, and out of love for their family and children, they stayed with them in order to preserve the peace and not hurt them. Affairs eventually hurt everyone involved. There are many reasons that they happen.