Hi Olman,
Interesting question. Human Beings can change if they want to, in many cases. However, as you age change will definitely happen as I'm finding out at age 79. Your energy isn't as good as it used to be no matter what you eat or how much you exercise. Your skin wrinkles and your hair may turn gray. Luckily, my hair hasn't turned gray yet. Your familiar world starts changing. My husband recently died. My good friends also died as did the neighbor's cat who really liked me. I'm glad that my husband and friends and yes, the cat are all up in Heaven and out of pain. But now there's another change, I'm lonely. About all you can do is give all your cares and troubles up to God. I did and it works. Things are getting better for me. One good thing about God is that he never changes. He is always there for us.
Thank you for this interesting subject!
PML