This emotion starts at an early age for most people. We develop separation anxiety when we are forced to leave our parents or home for something like summer camp or a long visit with Grandmother. This emotion starts slowly and develops quickly into a sense of longing to return to home, or a similar place that we hold dear in our thoughts and mind.
This emotion is often present in adulthood as well. We long for a nostalgic place that will take us back to the warmth and security of times gone by. Generally homesickness is also about parental influence.
This influence is learned at an early age and for those that do not develop a close relationship with parents, homesickness doesn’t occur until later in life when a true home has been established and a personal sense of security has been established.
Homesickness is associated with family, friends, and personal material possessions in a place that emulates security and personal well being. It can be exacerbated by divorce or if someone you love has recently passed away. These scary and sad experiences may make you even more attached to everyone and everything around you, including the small things you don't even think about until they're not present.