Post Vacation Depression

why do people gets so depressed when they come back for vacation?  I just got back from the best vacation of my life and came home all depressed plus my aunt not even here with me:(  I cry my self to sleep every night and woke up every morning crying because not seeing my aunt right next to me:(  UGGGGG when is this depression is gonna be over.  I cant do this any more:( I need to see my aunt sooon.  Cant wait to go back during July to Celebrity my Bday over in Thailand:)