I know what you mean. I know I once had other parts down there, but I can't remember what it was like to have them. I used to wear boxers and let things hang free, but now can't live without the felling of having panties, which obviously you wear alot closer.
A feel the same way about my breasts. I have gotten used to having them, their weight, the way the hang forward when I lean. Not having them would feel more strange to me than having them, they are part of me, they are me.