Not only do objects and physical places change but people and their personalities change. People grow together or people grow apart. People mature or don't AT ALL... I mean, 0. People grow for better or for worse. People develop different personalities over time. And all of that can affect the way you see yourself and others. For example, throughout my life I have had many different friends until now when it seems I have finally found the best besties ever in a couple of ridiculously nuts people (you know who you are). And that's okay. That's life.
But please don't have a negative idea of change. Change can be good. I, for one, like change and think that every now and then it can be healthy to keep you on your toes (as long as you don't lose your "muchness"). I actually find routine can be kind of boring sometimes, which is why it's good to explore, try new things and be open to change... CHANGE CAN BE YOUR FRIEND! Don't be afraid of it but embrace it! Of course, always remember that change is neither good nor bad. What is good or bad is what we make of that change.