Parents often build their lives around their children, and it sounds like you were very important to them and they love you very much. It is a big adjustment for loving parents to get used to not having the child around that they put so much time into and were used to having around them.

I had a hard time when my daughter finally moved out. To me it seemed like one moment she was so little and the next she was leaving.

So it sounds to me like your parents just love you and like having you around. They miss you, that's all.