The world is a much more mobile place these days. Many people now work at home and telecommute to their office, but others still must report to a designated location for their work. While many work in the area where they grew up, some people may find work far away from their home. They might travel as far as the other side of the world for their job. This is difficult if they are in a relationship with a person that cannot leave the area.
Long distance relationships are difficult because there is no physical contact. While cell phone service, email and video chatting are now available, it is still not the same as being with a person. People in these types of relationships must work hard to maintain them. Being alone, without that special person by their side, is often lonely. It takes two very dedicated people to keep their relationship going when they are half a world apart.