Most Helpful Girl
That's life for ya. As you grown older, you naturally begin to grow apart and take different paths. I had different friends at different stages of my life and let them go accordingly. We all eventually grew apart when what kept us together was no longer in the picture.
Family is slightly different, you do maintain that close relationship, but life, distance, responsibilities and time get in the way of maintaining that closeness and eventually you don't even notice that it's been weeks since you've spoken and/or seen your own parents/siblings.
Most Helpful Guy
If they have so much meaning, are you sure they know how you feel? Perhaps, you should ensure that they don't feel like you're taking them for granted and pay attention to their needs.